Carter was a pretty good person, at least post-Presidency, can't really speak on how he was in the White House though.
Reagan, otoh, was irredeemable all the way through, given while he was in the White House, that guy effectively destroyed the middle class, created the current disaster that is unaffordable post-secondary education, and created the current credit score system among other atrocities, not to mention that whole Contra business.
Yes, really, if it weren't for Reagan, there wouldn't be a massive and progressively-widening gap between the bottom and top of society, it would still be possible to get affordably educated, and people wouldn't be getting completely screwed by bad credit.
For a perfect foil of everything the US has stood for for at least the last four decades, look at most of the EU having universal healthcare, having an actually regulated education sector where for-profit grift schools like University of Phoenix or even the late ITT Tech or EDMC and its subsidiaries, wouldn't have ever been allowed to take root to begin with.