I am 97% sure we will find incontrovertible signs that microbial life existed on Mars in the past. I hope that Perseverance is the one to find it. I am 23% sure we will eventually find signs of active microbial life on Europa. It's just a simple matter of chemistry and time, in my mind. And, once confirmed, I think it will be a minor footnote for the general populace. For science it will be an important milestone. But for the general population I think a small portion will have a bit of sobering perspective on the enormity of time; how long it would take for evolution to turn microbes into human beings. Right now, in America at least, we are taught there was a ball of fire and gas, and then things calmed down and single-celled organisms emerged from the goo, and then dinosaurs, and then Columbus discovered America. They are all equidistant points on the timeline. But a discovery of the evidence of life on another planet - possibly long before there was life on Earth - would cause the "think-ier" people to have a fresh accounting of the timeline of history, and the full scope of what 3 billion years actually means. That will be exciting for some, and unnerving for others, I suspect. And there will be the dogmatic minority who cling desperately to their religion(s) and deny plain evidence. But they don't factor into my life or thinking, so I don't really care what they think.