I think it’s a combo of two things.
One is some sort of pathological need to shore up her legacy - to become more than just a historical footnote brought up by wonky types who like to discuss politics. She feels she’s a failure and doesn’t want to be remembered as such and it causes her to seethe. This part is on her.
The second, well tt53 says it best:
The righties won’t let her slip into obscurity. She’s the perfect Bread & Circuses/whipping girl to distract us from how inept the entirely Republican-controlled government/President Trump has been to this point. I mean, both parties are a corrupt mess, but HRC at least keeps the right-wing base distracted & angry - anything to delay the inevitable questions from the voters: When does construction start on the wall? When is the 1st installment from Mexico due? How come Obamacare hasn’t been repealed?
They better hope that they’re functional enough to pass some kind tax legislation. I mean, we’re talking tax cuts here, right? The one unifying issue among all Pubs. If they can’t, even HRC might not be enough of a distraction.
But yeah, Lou. I’m with you. She had her chance. Time for her to go away …