Only because we have a firm understanding of their legacies. If I made this list again in 40 years there's a good chance he's in 1st place.
Squirrelknight
From bad to worst:
10th: Nixon
9th: Bush
8th: Wilson
7th: Hoover
6th: Tyler
5th: Harding
4th: Pierce
3rd: Trump
2nd: A. Johnson
1st: Buchanan
He's in the bottom ten, but is currently being overshadowed by someone in the bottom five.
That makes him look better by proxy.
The words "America" and "learning" are basically antithetical at this point.
Nothing will be learned from all this. They'll elect some new republican monster sometime in the 2030s if not earlier.
Thankfully (or maybe unfortunately is a better word for it), they've done a lot more illegal things than treason.
I think democrats have more than enough things to prosecute them on if they want to. Real question is if democratic LEADERSHIP wants that.
Man, why are all the GOOD 80 year olds dying while the worst 80 year old gets to keep ruining the world?
He's the best thing to happen to quite a lot of countries not named USA...

Core childhood memory. I remember getting this game for Christmas 2004 and playing it religiously until the sequel came out a year later.

That's just the animal version of the wet bandits.
Some might also be in the lost & found.
He's a professional loser. This is what he does best.
That, and rape little girls.
He'd be in the bottom 15. The problem with ranking Reagan is that most of the big issues with him didn't become fully apparent until long after he was out of office. When you make a list like this it's kinda hard to fit all the awful US presidents in a top 10.
All the president's between 1840 and 1860 alone deserve to be somewhere in the bottom 15 for endlessly supporting slavery and setting the stage for the civil war, which makes fitting Reagan in kinda difficult.