The omicrons ended up as just robots and they couldn't grow or change so all they could do was mass murder everything because it was the only solution that resulted in 100% chance of safety. The ones we meet are just part of the ultima thule memory museum of exterminated species as far as i know so they're not even the real thing.
the endless are just... memory recordings kept inside a habitat. Being able to simulate feelings does not make it real. Even at the best of times they were just turned on or off depending on who was visiting. Keeping them "alive" required killing actual alive people on a regular basis too. It's really kind of a black and white situation