I think "killed, enslaved, and/or tortured most of the citizens of the regions it's already captured" is an exaggeration. That is not to deny Russian war crimes, which are clearly large-scale and horrendous. But I don't think the majority of people in those regions have been killed or enslaved.
I'm a big supporter of Ukraine and have donated to the war effort and hosted Ukrainian refugees.
What happen to Bucha and Mariupol? Why did they get wiped off the map? Was it a tsunami?