that still leaves a huge margin for other civilizations on other planets to have evolved, progressed, and died out, long before we even evolved.

That's what Hawking argues, but his guess for why they're dying out is someone else nukes them when they detected.

The same math makes one wonder why aliens aren't here already. There's billions of stars within a few thousand lightyears. If one of those stars was similar to earth, but cooled just 1% faster, they'd have had a million years to spread out or leave some kind of mark on the galactic neighborhood.