I understand the counterargument, although it seems clear that the idea of “Ukraine” along with the culture and people are systematically killed.

And the death toll is suggestive of genocide and not just strategic bombing. Mariupol alone had past 130,000 casualties; its people were killed without regard. And massive grave sites have revealed torture, reminiscent of ethnic cleansing elsewhere. So, I think the term is appropriate not just because of the death toll but also because of the method of killing.