Is the Fermi Paradox that paradoxical?

You've probably heard of the Fermi Paradox.

One day, while visiting the Los Alamos National Laboratory, physicist Enrico Fermi wondered aloud,

"Where is everybody?"

And by "everybody," he meant aliens.
From that informal question and the discussion that followed with his peers, others, including Carl Sagan and Michael H. Hart, developed a theory that now bears his name and is known worldwide as the "Fermi Paradox."
Before we continue, note that, while they are our most prominent (almost) contemporaries to have theorized the problem, others before them, including Fontenelle in the 17th century, have asked the question in one form or another in their writings. So it's not a completely new matter.

In short, the paradox states that given the number of stars in our galaxy (between 100 and 400 billion) and the likelihood that there are even more planets, the probability of extraterrestrial life existing has to be close to 100%. So why haven't we found anyone yet? Sure, our best telescopes can't see details on distant exoplanets, but why haven't we detected radio signals or similar communications? And why haven't they found us or contacted us?

This is essentially the Fermi Paradox, for which many theories have been proposed to explain it.

As a side note: about 6,000 exoplanets have been found in a bit more than 4,400 star systems as I’m typing these lines. We've found a few dozen candidates that could support life as we know it. However, remember that the actual number of such planets is likely in the billions, in our galaxy alone.

Obviously, I'm not an expert, but I sometimes find many of the hypotheses about the Fermi Paradox to be overly "Earth-centric" and/or too inspired by science fiction.
Don’t get me wrong; I love science fiction. However, I also think that, while it is important for helping us imagine possible human-centered futures, science fiction is not so different from fantasy when it comes to aliens and extraterrestrial life. For obvious reasons, science fiction authors lack the facts necessary to ground their imagination when dealing with aliens.

For example, I’m thinking of hypotheses that state some advanced alien civilizations exist, know about us, and are observing us. However, they don't make contact because we’re not advanced enough (the Zoo hypothesis comes to mind). I mean... Why not?
However, it sounds a bit too "StarTrekky" for me. Don't get me wrong; Star Trek is great. However, it's not exactly realistic science fiction.

There are also hypotheses that advanced civilizations hide because there is a violent and predatory civilization in our corner of the galaxy that colonizes, invades, and destroys every other civilization it finds (the Dark Forest hypothesis). Maybe. Why not? But I don't know. It sounds like something white humans would do. But if there were such a violent, expanding, and well-known civilization in this corner of the galaxy, wouldn't they have found and eaten us by now?

There are dozens of other hypotheses, some more probable than others, but they are all based on unprovable assumptions as we just lack the necessary facts.

One explanation of the Fermi Paradox that I find interesting is the Great Filter theory.
It states that, at some point in a species' life, something will prevent it from achieving interstellar travel. This would explain why there are either no civilizations in the universe that can achieve interstellar travel or why they are very rare and unlikely to discover each other.

The question, of course, is where in the course of life’s evolution is that filter located? (Assuming that life develops in similar ways throughout the universe.)
The filter could occur as early as the evolution from unicellular to multicellular life forms. This evolution may be rare. In that case, we are the lucky ones for having passed the filter. However, we also could be the only ones who have passed it.

It could also be that any civilization that becomes technologically advanced enough will eventually self-destruct before developing interstellar travel. And the current state of our world could prove this point and we may be about to reach that filter.

There are other possible locations of the "great filter" throughout a species' lifetime, but these two are probably the main ones.

I hope that one day—hopefully while I'm still alive and before our civilization collapses—we will develop telescopes powerful enough to observe life (or signs of life) on nearby planets. It would be great to find civilizations that are roughly as advanced as ours, but I'd also be happy to find something like their dinosaurs.

Yes, there are many hypotheses, and one of them may be correct. However, I think there's an even simpler explanation that I rarely see mentioned directly when people talk about the Fermi Paradox.

It's about space and time.

Unless something like hyperspace exists, which is unlikely, interstellar travel deals with distances so vast that, even if it's technologically possible, it's logistically very difficult, if not impossible to achieve. Traveling to another planet in another stellar system would take decades at best, most likely much longer. Would it be possible to return home? What would be the point of expanding and colonizing nearby stellar systems if the planet of origin can't really communicate with its colonies and benefit from them? Would any civilization want to attempt such a trip in those circumstances?
It's not impossible. After all, some past human civilizations have done seemingly crazy things, using an insane amount of resources for goals that seem pointless to outsiders (the most obvious example is probably the building of the pyramids; both in Egypt and in Mesoamerica). So, who knows what crazy, seemingly wasteful, and pointless endeavors an alien civilization could engage in?

Of course, they don't have to send members of their species; they could send automated probes. After all, we've done so with the Voyager program, even though the two probes are not fully automated. And, we'll soon lose contact with them forever. Also, it is estimated that they will reach the stellar systems where they're heading — we know which ones — in about 40,000 years.
Perhaps aliens are sending probes. Maybe. But we're not seeing any signs of them. It's true that we've been able to detect and recognize interstellar objects in our solar system for just a few years; and there must be many objects that we haven't detected.
I don't want to veer too much in that direction, because I want to keep this post grounded, but could some UFOs be probes?
Maybe. Then again, probably not.

In any case, I think we can all agree that the vast distances and slow travel speeds would prevent civilizations from different stellar systems from visiting or even simply contacting each other.

I think there's another hurdle that I rarely see mentioned, and it's not mentioned enough in my opinion. To me, the most obvious hurdle is time itself.

What do I mean by that?

Let's use our own planet as an example. Earth is about 4.55 billion years old. That's quite a long time, but some stellar systems and their planets are even older, Kepler-444 is estimated to be 11.2 billion years old. Recorded human history is only a few thousand years old. The oldest writing systems we know of, the Egyptian and Sumerian systems, are less than 5,000 years old.
That's only 0.0001% of Earth's lifetime!

So, even if many civilizations have developed interstellar travel, even if many extraterrestrial civilizations have actually visited Earth, there is a 99.9999% chance that they did so before humans were able to record it. And there is about a 99.993% chance that it happened before humans even existed.

For me, the Fermi Paradox can be explained by an incompatibility in timelines, more so than by some far-fetched hypotheses or even the Great Filter hypothesis. Not only does a civilization needs to reach a level of technology that enables interstellar travel — and preferably, fast interstellar travel — but they also need to be lucky enough to arrive on our planet (or any other) at the exact moment life forms on that planet are also advanced enough to enable contact and communication. I doubt the dinosaurs or unicellular life forms were great conversationalists if Earth was visited during their time, which is much more likely than a visit in the last 5,000 years.

In conclusion, it seems self-evident (that's not a very scientific approach, I know) that even if the chances of extraterrestrial life existing are close to 100% and the chances of intelligent, advanced extraterrestrial life existing are non-negligible, the chances of two of them meeting at the right place and time are probably close to zero.

Perhaps the history of the universe is just a long series of missed encounters.

What do you think?