Recently, in the accelerated flight mode, I came across a space monster, a creature similar to a jellyfish. It radioed me and told me that it was lonely. I tried to shoot him, but it was useless. Is this some kind of quest or another blank for the future?

A lot of space encounters were added in them most recent update. Some of them you can interact with and some seem to be just for flavor, like this one. There has been speculation that Hello Games may do something more with them in the future but for now, they're just a curiosity.

I hope in the future it will become another interesting story, it would be great; in the game , all intelligent characters are only humanoid, and life is much more diverse

I think there's another Jellyfish you dont communicate with, but shoot it instead. It drops something (I won't spoil it)

There's also a similar Jellyfish which is part of a new mission.

We needs that creature in quest "living ship". If you have right stage, you can communicate with it and obtain "live water".