I think It's also about power and influence. He gave these people, who had no power and influence in their life, the sentiment that they had a political power, and not only the elite. They have been able to influence political themes and promote their beliefs, whatever <deleted> it may have been, they have been kingmaker at primary elections, etc... of course, they have been often following instructions and even been scammed, but it doesn't really matter to them.
Even if Trump leaves, they will want to keep that influence.