I'll add that the sun is a 3rd generation star which are the stars that have planets with lots of heavy atoms like iron and other important to complex chemistry atoms. The sun is thought one of the eariler such stars.

Combine that with it being highly probable that light speed really is the upper limit for the universe. So we are among the first planets likely to be able to support life and and all the others are very far away.

So we are probably among the first batch of life in the galaxy and all the other life is likely very far away. It's not surprising we haven't seen any signs of it even though there is probably a fair amount of it out there.