the reason liberals call the ukraine was a genocide is because war is so normalized to them that calling it a regular war isnt enough for them, they have to call it genocide to convince themselves this is different than what libs themselves want to do
Libs frame all their political enemies as genocidal. It's the only move they have and it generates more sympathy than normal war, because they can't pretend to care about every war on Earth. They certainly didn't care about Yemen.
Also it helps draw attention away from why wars happen. Liberals believe the world moves on personal animosity and beliefs. Putin isn't retaliating against NATO or securing sea ports or energy resources. It's not actions that can be put in a material framework. No. He's personally, individually bad and hates Ukrainians as an ethnic group and so any action against Russia is justified.