My best guess is transhumanism (or transalienism) is the answer to the Fermi paradox. That physical forms are so ill-suited to interstellar travel that galactic civilization is only viable in species that evolve away from them.

I like to think there are aliens out there that started as animal-equivalents but are now algorithms. Like, not even algorithms running on giant gas-cloud supercomputers, not even algorithms being beamed through space as radio waves, just the fact of algorithms.

By analogy to things like HeLa and CTVT, I could totally imagine that Maxwell’s equations or the Planck constant began as something like humans. Or that the ultimate progenitor race was time, and the Big Bang was something like the Cambrian explosion.