Our sun is very metal-rich, which means it is at least a second generation star, at most a third. Given the billions of years it took for our solar system to form, and for life to evolve on one of its planets, the idea that we are amongst (if not THE) first intelligent species in the entire universe is not entirely unreasonable at all. Life on our planet is almost certainly amongst the first life form in the universe in general, if not, once again, the first life to form. This is all from the basis of our understanding of evolution and what is required for life to exist in the first place, however, and it’s entirely possible that other worlds have experienced conditions of accelerated evolution. That still doesn’t mean, however, that intelligence was an element of that accelerated evolution. There are many things that make humans human, not the least of which is intelligence, but also our physiology in general.
Personally, I think the most likely scenario is that if there is other intelligent life out there, they are quite likely around about the same stage in development as us, if not an earlier stage. If they’re more advanced, they can’t be that much more advanced. For one thing, when we look at the universe, we can see a whole helluva lot, and we don’t see evidence of the kind of tech that would indicate a space-fairing interstellar civilisation. But maybe we’re not really looking for the right thing.
At the end of the day, all we have is theories, but based on the age of the universe, and the time it took life to develop on our planet, in our solar system, and the time it took for our solar system and planet to reach a point where life could even begin to form, I’m comfortable with the idea of us being the only intelligent life in the universe, if not one of many with similar understandings of the universe. There could well be another species out there on a distant world looking up at the stars and wondering, “are we alone?”
Everyone thinks of aliens as being vastly superior to us in every way because it makes great movies. I prefer the idea that they’re probably not that dissimilar.