I wonder about alien environments comparable to some on Earth.

The main thing about life elsewhere is that it must begin somehow.
This has happened on Earth, and later on, it adapted to other kinds of environments, sometimes similar to other worlds. The problem here is that those life forms did benefit from conditions suitable for life, even if later on that life had to adapt itself.
I'm not sure an environment not suitable for life can see it emerging.
It has to start in favorable conditions. Then it can adapt.
It's the same with growing human beings: there are many dangerous environments to babies, but no more to grown humans.
Raoul