Hope we find out someday. The laws of physics are cruel-- maybe someday we can see everything in a 100M light year radius to us is devoid of life, but theres still the other billions of light years where trillions of dice rolls are happening for a chance at civilization.

I am reminded of those few galaxies in Bootes Void who legitimately wouldn't be too wrong in thinking their galaxy was the observable universe until they could see beyond the dark.

Why would Boote Void residents not see all other galaxies? It’s just a relatively low density space nothing special about it. You’re probably thinking of Barnard 68 - dark nebula, and it’s too small to host a galaxy.

Sans fossil fuels, wouldn't we just have figured out how to scale something else? Ethanol maybe?

I think maybe we would have had slow industrialization until we figured out fission, solar PV, and good batteries.