After all consider the past 500 million years on our planet and how our species has only has been around for a tiny blip of that time.
If that is the average amount of time it takes on other planets then we might never meet another species since they could long be dead or not even around yet.

Our universe is so vast that it takes forever to get information.

to another in a reasonable amount of time.
Even then though the problem is still time as by the time another species has evolved that would be nearby such a species could long be dead.

and second, we're looking via old technology. Any BEMs out there worthy of the name are using quantum entanglement or something so far out there even wild eyed theorists haven't speculated about any of it.

Or they're at about our stage of development and are gawping up at us, wondering if they're all alone.

In the meantime, it's more likely a function of not knowing how or where to look than of being alone in the universe. It's such a big universe. Of course, add to that the fact that we can't communicate with other intelligent species on our own planet, and we share a planetary point of reference with them. Thinking we can communicate with life we'd be unlikely to recognize as being alive and with whom we share no planetary point of reference is ludicrous.