Right now he's hovering between Carter and Hoover but not Buchanan losing the Union levels yet. I doubt though Trump will be a great or even good President at this point. The circumstances around him are too grave to warrant him being a good President.
Basically, there's no recovering for him? He either is removed or defeated for good reason or serves all the time and just leaves carnage....but doesn't become an existential issue. Tgis is most likely. Best case, he is an "average" president that gets reelected but doesn't change America's course or does become that next person who breaks America.