I think reality is that whenever this conflict ends, if any part of Ukraine is free it will be in NATO almost instantly. But doing it while there is a conflict sort of creates a scenario the treaty didn't account for and Russia hasn't accounted for. And you don't want those kind of not-contemplated scenarios to come about when there are nukes involved.
Ukraine can’t join while in an active war. Ukraine is also going to lose, so Russia is going to get to dictate the terms of the war ending and I don’t see that allowing the western side of the country that will be left to be in NATO.
Russias terms will be getting to keep stolen land. The last time they promised not to invade as part of a treaty, they did. Twice. Ukraine is going to get protection at some point for whatever is left of their country. And they’ll try to get support in a way that will attempt to minimize relying on republican promises. NATO membership would fit that bill.
I figure Russia will take the eastern territory for sure. Then they’ll have a neutral territory in the middle and then western territory of the new Ukraine with their own government.
It's a possibility. We have been doing the Nuke dance with Russia as long as I can remember. And I'm old. I will admit that Putin worries more than the others. According to this, Ukraine joining NATO has been discussed since 2008. My take-away is the recent comment made by the NATO dude is nothing new.