We have seen no evidence for alien life. If this continues and it turns out intelligence is rare, we will most likely expand faster and faster, effectively seeding the entire galaxy with life in a short (relative to the lifespan of a star) time. There should be a 'We
are the ancient aliens' option. Though this is unlikely, as we are living around a 3rd or so generation star, and even still it took a hell of a long time for multicellular life to evolve. Life existed since around the Hadean just after earth's formation, though it took billions of years more for life to grow to the required complexity for multicellular organisms to arise.
If that's not the case, and intelligent civilizations number ~10 to ~100 in the galaxy, we will still likely be far enough apart that barring FTL travel (which, let's face it, is so counter to known physics that there is a good chance it is entirely impossible), it will take tens, if not hundreds of thousands of years for human-spawn to reach them. At the point, human-descendants in different regions of space will be so different from one another that aliens with a different evolutionary root won't be much more different than those for whom we are ancestors. There is no 'unified humanity' concept when it takes several thousand years for signals to go from one colony to another on the far side of human-spawned civilization.
Further, if they are actually really advanced, we probably wouldn't even recognize them as living, let along intelligent. And outside of study, we would be of no use to them. At which point they would either go on their way not giving a crap or instantly euthenize the planet using tech as or more advanced than nanobots.
We humans possess one undeniable talent; we are stubborn as all fucking hell.
What is this based on?
Movie tropes. We actually give up really damn fast, to the point where the admiral trait of 'willpower' is seen as an admiral trait. For the most part, we can't even bring ourselves to do things we actually want to without great prodding. Sort of like that programming project I started and haven't worked on in a couple weeks.