And yet most actual Congressmen have a high approval rating within their district. Incumbents have an extremely high return rate.
The problem is never your Congressperson. It's always because Congress is filled with other districts' Congresspeople.
I don't think you'll fix that by un-gerrymandering. If anything, I bet you'll get even higher approval ratings for the incumbents, since you'll have fewer "cracked" districts (boundaries drawn to make a group a minority in two districts instead of the majority in one).
Ending gerrymandering might get a Congress that better reflects what people want. But mostly, what people want is for "the other guys" (whoever is not in your party) to win.