Factually no one has a clue about how big the universe is. The hubble looks as far and deep as it can and all it sees are endless galaxies. There’s probably life elsewhere. But you arent going to pick up tv signals from a trillion light years away.
Hubble is wavelength limited, not sensitivity limited. Due to the expansion of the universe, and cosmological red shift (as opposed to Doppler) the most distant galaxies are redder than Hubble's instruments can see. The new James Webb Telescope will not produce the awesome color images that Hubble did, but it will be much more sensitive and tuned to much longer wavelengths.