Yes, but if someone is off by just one percentage point, then they're 13 million years ahead. There needs to be something so unlikely about sentient life, that it only arises approximately one at a time in each galaxy, or the Fermi paradox would apply.

This hypothesis works best if we propose an extremely narrow developmental range.

Of course since we have basically no data, we can't actually argue either way beyond vague hand-wavey speculation. You can't calculate standard deviation from a sample size of one.

In general, sub percentage point uniformity is taken as evidence of a very strong synchronization mechanism. The extreme uniformity of the cosmic ray background was taken as evidence of inflation, which is quite an extreme position, if you look at the numbers.

That such a synchronization mechanism should work with such precision over the entire universe seems very unlikely. Filtering would not require synchronization, so that seems much more likely.

The only way I can imagine it being that synchronized is if evolution itself is somehow tightly coupled to cosmic inflation.

Here's the speculation in more detail:

Evolution can be viewed as an information transfer mechanism that learns about the universe and transfers that information into the genome. (This is one interpretation found in evolutionary information theory.) As the universe inflates there is more total information in it, and therefore more information for evolution to learn. At certain points, a kind of information density "critical mass" is reached and phase transitions occur: the emergence of life, complex life, cooperative/multicellular life, higher order intelligence, industrialization and complex society, etc. Since the total amount of information in the universe is (we're speculating) tied directly to the arrow of time, this occurs simultaneously everywhere at approximately the same time.

Again this is hypothesis bordering on speculation since we do not know of any mechanism that directly couples information content to cosmic inflation like this, or even how we would go about measuring such a thing objectively. For instance it's not possible to differentiate between random and encrypted data using Shannon information measures, so what statistic would you use?

Then I'll invoke Occam's Razor. A simple filter explains the situation more cleanly, and doesn't need the addition of a wild-sounding mechanism that affects evolution that's attached to inflation.

Furthermore, if it has such a powerful and pervasive effect on evolution, why haven't we already discovered it in our studies of evolution to date? We live on a planet chock full of evolving life.

I think the Fermi paradox has a hidden assumption, that we are intelligent enough to detect aliens. We couldn't detect that the earth revolves around the sun till quite recent in our (genetic beings on earth) evolution. I say give it a few years, we'll figure out that aliens are too alien right now to us. Computationally speaking, our brains are quite limited, though we have recently gained the ability to share ideas across the internet. Nice hearing from you cousin!