Trump was probably a Putin plant and had he been in power, Ukraine would have been finished. The chinese themselves are very pragmatic. They will take full advantage of Russia's weakness. They are gobbling up or will be gobbling up Russian resources for pennies on the dollar all the while Chinese companies are scaling back operations in Russia. They will have their cake and eat it. The Chinese have already stated that they recognize the territorial integrity of Ukraine including DPR/LPR as being part of Ukraine.
This will go down in History as a gross miscalculation by Putin vs. Bad luck. They needed things to go their way, Trump as president, weakened EU, they spent years setting up internal EU divisions and playing them up, got the UK out of the EU and did arguably weaken NATO politically. If the Poles and the Baltic states not forced NATO/EU into the fight, Ukraine would not have the support it has. Keep in mind the Polish govt. is no saints either and are also populist Right wing idealogues.
This was is never about Ukraine in the West. This war, for the West, is to drag Sweden and Finland into their camp.
Were Russia tempted to attack? Perhaps, but Putin would probably be either delusion or an useful idiot to attack Ukraine had this been a Western Trap. Think about it like this, for a normal person, you threaten me with violence, and I look for someone to protect me from you, then you literally attack me to try to force me not to find protection. That's not logical. And then you threaten my friends and neighbour. What would be the normal reaction? Me, my friend and my neighbour will all go and seek protection...Hence Sweden and Finland wanted to dump 130 years and 70 years of neutrality and join NATO.
There are no way Russia can come out ahead in this war had they actually attack, because as it will simply make people wanted to join NATO more, and as predicted, this shift happened in Sweden and Finland and now Moldova are also contemplating for NATO membership. This is going to back fire and everyone with a functioning brain can see it. Yet Russia still attacked.
There are numerous "Predication" on why Russia attack. From the very simple Putin saw US pull out of Afghan, he sees it as weakness and want in, or he think invading Ukraine would be like Crimea, quick and bloodless and the west cant do anything before his operation is completed, to he is terminally ill and he just don't care or were not able to make sound decision.
On the other hand, if he wanted Ukraine, what he should have done is wait for 3 years until Biden presidency is over, and see if he can get Trump back, if not one of his follower, then either subverts the Ukrainian government or waiting for a weaker NATO position to attack. But then who knows, he may not have 4 years.....
On the other hand, one wild card not too many people can see is the war bend together the entire Europe. Europe like US were divided between Left and Right, namely Nordics , Germany and Central Europe. This war bring them together and bend them toward the same man, Putin, this is unforeseen, no one would have thought the EU will give such an effort united against Putin. That I think even comrade Putin failed to see