It's not who is most evil as you are right, there are few more evil than Lil Kim. It's who has the capacity to end the world and who is least stable.
Lil Kim can toss a couple nukes and kill a couple million people. Which is absolutely frightening and terrible. Old Donnie Two Scoops can erase humanity from the Earth with his mistakes. So the stakes are FAR higher.
And I've seen enough that it's not just a matter of intentions, I honestly think there is senility involved which is only going to get worse. With Reagan, especially towards the end, there were senility concerns but you knew that even with decreased mental capacity the overlaying human was a decent individual and that he had a very smart staff helping. Here...neither is the case. The worst staff in history (that's not an opinion, a simple fact based on turnover) combined with what you would very kindly say is the most flawed human we've had in office. And THAT'S who is making decisions that can end humanity.
It's not just apples and oranges when comparing Lil Kim and Old Donnie Two Scoops, it's comparing a rotten apple who could make you quite sick if you do something dumb like eat it but for the most part is just sitting their ruining the other apples underneath it and a rotten orange who can END HUMANITY.