I don’t know, if this is worth arguing over. Depending on how far advanced you expect such a life form to be, obviously they might be capable of things that we currently consider impossible. But well, to illustrate what I mean:

• The next galaxy is the Andromeda galaxy. It is 2.5 million light years away. There could be life over there right now, but we wouldn’t know, until about 2.5 million years from now.
  Compare that to the emergence of modern humans, which was 300,000 years ago. We didn’t start sending out radio waves until some generations ago.
  None of this means that it’s not possible for life to have existed on some planet 2.5 million years ago, so we’d be seeing their radio waves right now, but even then, we might interpret them as background noise.

• The next star is Proxima Centauri. It is 4.24 light years away. So, we could see things from there in 4.24 years, which is pretty good, although still absolute hell of a delay for exchanging messages.
  But for them to actually visit us, even if they go at 1% the speed of light, that would mean they’d need 424 years of travel time. With little sunlight or other energy sources on the way.
  And 1% of the speed of light is an insane 10,800,000 km/h. Compare that to the fastest man-made object, the Parker Solar Probe, which is expected to go 720,000 km/h, when it closely passes by the Sun.

Basically, we can be extremely generous with these examples and still see practically insurmountable time frames.

Worm holes could theoretically exist. Maybe a sufficiently advanced race could defy physics as we know it. But if they can’t, that’s a pretty good explanation why they’re hiding.