First of all, to me, a former president would worry about bigger picture things than how state legislatures hack up districts. I would think he would jet around fighting hunger like Bono or some such noble-sounding (but not particularly practical) task. But I guess raw political power is what this guy is all about.
Anyway, gerrymandering is not so easy to “correct”. Concentrating demographics to create safe districts for one party also tends to make the other party’s districts safer for them. And if the Dems aim to create more districts than can compete in, that will likely reduce the number of safe Democrat districts. Practically speaking, since GOP-controlled legislatures will not listen to them, I guess they are talking about more litigation. But I think even liberal judges have a hard time figuring out what kind of gerrymandering works out “best” for the Leftist grievance groups.
Gerrymandering is implied to be an ugly word. But absent a square-shaped state with a completely homogeneous population spread evenly so the state can be divided into neat little squares, drawing the lines for legislative districts is necessarily a political process.