Our ability to discover planets is very new to astronomy as is the search for signs of ET life via new planet discoveries.
I think our criteria for “life” is very limited at the moment. Anthropomorphic bias: Things called “living” seem to all have at least SOME parallels to us humans.
So yes, I think we’re missing a lot.
Agreed. I think we need some advances in bridges between chemistry and biology. There’s some speculative work done. For as long as I know there’s always been a subset of scientists who believe that some forms of crystals may actually be living.
The borderline of life/non-life is a fascinating field.