A possible higher intelligence does not necessarily equal god, it does not even come close to fulfilling generally accepted definitions for the word “god.” You can believe in the possibility of a “higher intelligence in some form or another” and still title your self an atheist.
Also for clarification, define “hard atheist.”
I agree in part, I too think it would be foolish to deny the possibility of “more inteligent (sic) than humans” out there somewhere, at some point. The known universe is incredibly vast, and there maybe a whole lot more “unknown” universe.
However, we are now just talking about advanced intelligent life, somewhere, at some time. This is no longer a conversation about “god.” Or atheism. Unless you are trying to say this intelligent life played some sort of major role in creating life/humans right here on planet earth.
This instead is a conversation about “intelligent life elsewhere” which in my mind, is also a rather foolish conversation. May be fun to talk about, but has zero actual implication/consequence on anyone’s life here on this planet. At about the same bearing as arguing if a rainbow farting unicorn god exists or not.
Still happy to discuss this topic, pointing out the enormous contradictory flaws of just about any god or “intelligent life somewhere” conversations remains a fun exercise to me. If anything as insight to why people think the way they do.