As far as my thought goes. This is probably what Putin have done wrong.
NATO were never going to come into Ukraine assistance except for Arms transfer, the request of No Fly Zone is a no brainer, Zelenskyy knows it, Putin knows it, everyone in NATO knows it.
So if Putin is smart, he should have wait until Zelenskyy losing steam on NATO (like the address he has done yesterday) and when he does, gently remind Zelenskyy that NATO is not coming, and they weren't coming from the get go and he was living in a dream for thinking NATO is going to bail his country out. Everyone in both side knows the American and European will at most just sit infront of their tele and say "How awful is this" and move on. So if Putin make the situation dire enough, and show them his hand, he would probably agree to most of Russian point. I would assume this is the reason why putting did not engage fully with the war in the first 7 days
That is not going to happen now because Putin used a hardline approach, which done too many thing that would cross the line not just to Zelenskyy but to normal Ukrainian. As I said before, you don't make friend with bombs. Which mean the more the Russia side shell civilian, the more you put them against Putin, and there are no way 200,000 troop (probably a lot less now as the war of attrition went on can control the entire country. Which mean insurgency at this point is all but certain, and this is not going to be driven by the EU or NATO, but simply people losing their home, their love one because Russia choose to target civilian instead of military target. Much like how Germany were at the brink of conquering British RAF but then they choose to bomb civilian, which increased the population resolve and gave reprieve to the military