Like many politicians, Xi is ruthlessly self-interested. His actions that allow him to consolidate power aren't necessarily in the best interests of China.
Yes, this sort of narrative plays a lot better when describing someone you're actively at war with. Along with the fact that you are always winning the war. Ukraine has been winning the war with Russia for about 9 months now, according to the media.
What media?
In the beginning most reporting was that it would be over in a week. Then Russia had that little blunder with their first offensive. Then again most reporting was that the russian artillery steamroller would squash the Ukrainians. Now most media favor the Ukrainians due to their recent successes. Also goals and frames of reference changed. In the beginning winning for Ukraine was not letting Russia roflstomping them. Now it is throwing all russian military out of their country.
It’s always in our interest to simply reduce our enemy to madmen or nazis, as it justifies our own counter aggression.
Yeah, Biden himself recently said that Putin is a rational actor who grossly miscalculated, because he was basically fed very bad and flawed intel. He may be blustering about nukes now, but the only way he would do that is if Ukraine turns the tables and invades Russia, or something similar.