I figured out

[magnetaress]

How to purge unwanted pops in endless space 2 without mods or micromanagement, efficiently, while, ironically benefiting from them.

Salusa Secundus is pretty easy to set up and get going once u got spaceports and chain gang. U can buyout improvements there to make the pops work harder. Just make it a system without warm food producing planets. And do not build food improvements. I found one with a gass giant and frozen ice world with some steategics. A pop or two dies every turn or so, so that there's always room for new arrivals holding in a queue of. Other ships from my other systems. The total cost on the empire is super cheap. Much cheaper than trying to manually manage pop growth or worry about "razing' systems. And I have almost a clean empire! It's great 👍 only have to tolerate filthy Xenos with pacifist ideologies a few turns and then they go to the prison system as cheap abundant labor leaving me with systems of loyal and perfect Sheredyn.

It's great!