He’s still only a private citizen at the moment, and as a private citizen, is yielding the considerable leverage he has to fight this unfair action. As President, he would have much more leverage at his disposal to hit back with and wouldn’t need to use his personal finances. It really ticks you off to see someone fight back, doesn’t it?
You conflate the issue. The issue is whether or not he will use his public position to advance his multi billion dollar global financial interests. In this instance, he intermingles both.
The claim is that Trump is not controlled by outsider money— the question is — is he controlled by his own financial interests?