True, I had forgot about how the restrictions here on earth might not need to be the same for alien life to be able to exist.

I'm not arguing against you though. When you look at the universe as far as we know though, there are places that might support life like here on our planet... and we know this because we find the same or similar conditions like we have here.

That's the way we currently search, find the conditions and there might be a possibility that the planet supports life.

Yet, even finding nearly the exact same conditions isn't a guarantee for life elsewhere, we've figured out that much already.