My read on this is Trump doesn't actually want to help Ukraine (he is buddies with Putin practically) but that Russia is doing so badly and has such a hopeless outlook that Trump in his cowardice has switched sides or at least has begun to genuinely play both sides to try to distance himself from being associated with Putin.
It also helps that Ukraine has demonstrated an undeniable value to the US militaries' investments and approach to war both in the modernizations undertaken to US weapon systems but more importantly in the original design of cold war weapon systems and their fundamental lucidity about the nature of future near peer armored conflict. Trump desperately doesn't want to be left out of the military industrial complex and the piles of money in it, especially because AI and crypto are utter bullshit.
This is why this slow "waffley" move to support Ukraine from Trump is so messy, contradictory and confusing.