>I've always thought of Fermi's paradox as ultimately a math problem, assuming a conservative amount of time between a civilization in one star system colonizing a neighboring star system, over billions of years every star system in the galaxy should be colonized by now.

I've never found this argument particularly compelling, as it seems too simplistic and ignores a vast number of possible confounding variables such as stars not being equally amenable to colonization, or even equidistant to each other, and the likely stability of civilizations over such timescales.

It seems far more likely to me that any civilization that colonizes another star sees diminishing returns given the risk and reaches some limit rather than seeking infinite, exponential expansion.

>The fact that we are not getting signals from the considerable number of stars that are within a reasonable distance is concerning. It does point to a great filter that we are not seeing or understanding. Or at least an enormous misconception about our universe.

For one thing, the observable universe contains billions of galaxies, which means the vast majority of stars are unreasonably distant.