Think about it. They support Ukraine by sending them surplus or aged weapon systems while modernising and funnelling money to their military industrial complex (with public support!). In return Ukraine uses those weapons systems to keep Russia tied up in a war, exposing Russia's most modern weapon systems and providing a huge amount of information on how to fight a drone war.

This is a great investment independent of what happens in or to Ukraine, basically they turn weapons they needed to replace or get rid of anyway into intel, new weapons, political brownie points at home and a weakened adversary.

China doesn't mind it that much either, though they enjoy it less because they had invested fairly heavily into Ukrainian infrastructure that is being destroyed. Keeping Russia isolated makes it easy for them to extra cheap oil & gas, push for pipelines that flow to China instead of towards Europe and also offload a bunch of their industrial surplus now that their requirements are winding down and the rest of the world is trying to tariff them for dumping.

So basically the problem is 1. is good for almost everyone except Ukraine and Russia. Trump for whatever reason can't understand that and just wants to throw a tantrum as is befitting for someone of his intelligence.