With regard to intent and what Putin has said, I have studied his features and have peer-reviewed academic articles on them, so this is my field. You should distinguish between his attitude to Ukrainian statehood and his attitude to the Ukrainian people, because they are distinct.
Putin has threatened Ukrainian statehood. He said a while back that if Ukraine tried to recapture Donbass by force, it would be the end of Ukrainian statehood. In his speech recognizing the independence of the Donetsk People's Republic and Luhansk People's Republic, he ran through how the communists had put Ukraine together from various bits, and then he said that if the Ukrainian authorities wanted decommunization, he could give them decommunization—which in effect meant unravelling what the communists had done and cutting Ukraine up. That is a definite threat against Ukrainian statehood.
However, his attitude to the Ukrainian people is very different. The Ukrainian people are continually referred to as a brotherly people, as one sharing the same language, the same culture, a common history; as one the Russian people are entirely friendly with, and there's no intent to destroy the Ukrainian people or Ukrainian culture as such. There is a keyword that's not been mentioned in the genocide convention list, the words “as such”. You have to be aiming to eliminate a group “as such”. No such intent has been stated in his speeches.
Moreover, he is vehemently anti-ethnonationalist. He has repeatedly denounced what he calls “caveman nationalism”, which is ethnonationalism, and he has repeatedly stressed the need and the fact that Russia is a multinational, multiconfessional, multi-ethnic society, and that this is a good thing.
Therefore, yes, he's definitely expressed threats against Ukrainian statehood, but as for an intent to destroy Ukrainian people, Ukrainian culture—no.