Trump doesn't actually believe any of the bullshit he spews. With him literally everything is transactional; a negotiating tactic; a calculated facade. The only thing about which he cares or has ever cared is his brand.
It’s less important if Trump believes his bullshit, I agree he probably doesn’t believe at least some of it. But the problem is his base believes it whole heartedly.
For further reading check out some @Reggie_Essent posts.
Grimm hasn't run across a conspiracy theory that he's ever disliked. He is clearly completely into the idea of rebellion (with or without a cause) and chaos.