Why is that inevitable?
Sine slight climate problems could have wiped out humanity (or recent ancestors) before we got a chance to spread over the planet.
The other primates are smart and have hands, but just don't seem to have the pressure and opportunity to become as intelligent as us.
And nothing else even seems close to becoming an intelligent, technological species.
I haven't seen any reason to presume the purpose of the environment was to make intelligence. The fact that only one species (and possibly its nearest extinct relatives) had been able to develop technology and high intelligence and millions and millions haven't seems like a slam dunk.
So, you think we are rare, that "millions and millions haven't", huh, (and I would ask you how you arrived at that conclusion) And, even if were, that, "one in millions", even one in millions could be very, very many, considering the entire universe that is...
As far as the conditions go, you don't think anyone had a hand in that...? And might do so in other places too...?
You don't believe in higher intelligence than us...? What makes "us" the "most intelligent" lifeform in the entire universe...?
What if ones began where we are now, where are they now?, or where would they be by now? How would they exist? In what form?,
Depending on where they are at, we could all be still in our infancy to them, as they once were (maybe).... I think they some of them went beyond of this realm, or one of them/us did, maybe after millions of years in a humanoid like form, evolved into something else... "Q" like maybe...
It's possible...?
Well, if life and intelligent life like us is not as rare as you think, you'd almost have to conclude that some lifeforms did develop into a higher state of being, if intelligent life or humanoid like life, is not as rare as you think, and it really hinges upon that...
God Bless!