Chris Rock in his first album had a great bit talking about former Washington D.C. Mayor Marion Berry, who famously was re-elected after being caught on video camera smoking crack. Rock's point was, by voting for someone so clearly unfit for office, any attempts by the African American community to fight for the District's population on health care, education, or anything else, was met with laughter by other politicians/voters who would shout, over and over again "mayor's on the PIPE"!
Like with much of Rock's comedy, there is a deeper meaning to this observation. Specifically, his story is a warning to any community who votes purely on a tribal or cult of personality basis. When it becomes clear that a group's political support of a specific person or party is unrelated to fitness or accomplishment, the rest of the political realm and voting public will never take you seriously. You will be thought of as cultists whose voices are unfit for inclusion in public discourse.
What will happen to Trumpers when he is out of office? Most of the rest of the professional GOP, especially those who have not chosen to take a stand against Trump in any shape or form ("because judges!", etc.) will seek to move on and focus on the issues that many of them believe in passionately. The problem is that in the face of these arguments a large part of the swing electorate may respond to those individuals with a "POTUS paid off a porn star!" or something like that, essentially using the same (flawed) reasoning that Rock referenced. This encapsulates one of the (many) prices I think the GOP will pay for Trump once he is out of office; by choosing to go all-in on perceived "in-group" loyalty and some policy wins they lose some core credibility with a voting public that they cannot simply ignore