It's actually incredibly likely that we're NOT.
But the problem is that simple physics gets in the way and the chances of two civilisations existing at the same time, within communication distance of ANY kind, and who notice each other and can do anything about it (beyond having conversations with 4000-year round-trip times), are infinitesimally small, even with a million such civilisations.
Basically, the limiting factor here is the speed of light - and if that's literally the limit of the universe, every civilisation that exists will basically be forever isolated from all others, just by sheer probability. It doesn't matter how advanced they get, how fast they spread through their galaxy, how many millions of years they last.... the chances are they won't meet another, or even catch a glimpse of evidence of their existence.
It's far more likely we're one of countless civilisations, even in our own galaxy, but almost certainly in the countless trillions of galaxies we can see, but that we'll never actually know that. The maths tells us so.
And if someone can "break the speed of light" (without tricks like holes in space, etc. but actually break the speed of light), they could probably also go spend all of eternity locating every civilisation that ever existed anywhere from the point they discover that, and basically visit them at any "time" in that civilisation that they desire. Would they choose 2024 Earth and humans from a universe of possibilities? Almost certainly not.
We're not alone, we're not the most advanced life. But we will likely be entirely unable to provide any evidence of that for the complete window of our entire existence. That's, by far, the most likely scenario for every civilisation in the entire universe.