What would alien life look like?

[ignoramus]

I have nothing to go by

We have numerous examples of non-simian species that are borderline. We seem to be the only ones to have stepped over the border thus far. Our existence may provide the selection pressure to nudge some of the others over the edge to full intelligence. If that happens, we are going to have the worst oldest sibling complex ever.

One big question will be whether or not the speed of light is an absolute upper limit. If it is then don't expect to hear from anybody soon. Intelligent life will be too distantly separated in both space and time. Our own light shell is less than 100 ly in radius and likely too low power to be detected against the noise at much more than 10 ly or so. It's also growing darker as we learn to communicate more efficiently, using fiber optics and directional lasers rather than belting signals off the stratosphere around the planet.

If light speed isn't an absolute barrier then our universe could be quite noisy. Efficient communication is vital to any form of governance, a fact demonstrated by every empire that has ever fallen. Anybody with FTL travel should also have FTL communication. They may also have sprawling empires spanning galaxies. SETI hasn't found signs of intelligent life yet because ET doesn't phone home with anything that plods along at the speed of light.

Is it feasible to extrapolate that because we haven't decoded anything yet from space means that there ultimately is no FTL comms capable or just no one to send it?
Or they're a lot further away. I mean, take 2 cut lunches with you farther away! And to extrapolate further, no FTL comms probably also suggests no FTL travel.