Both sides love to gerrymander, and love to complain about the other side doing it, hoping nobody will pay attention to what they’re doing. It’s part of why the system is irretrievably broken and cannot be fixed as long as parties exist. Parties will always be loyal to themselves first.
The difference being, when Democrats in power do it, Republicans try to win elections the best they can by persuasion and meaningful debate with an eye to redraw these according to their interests. When Republicans in power do it, Democrats find a sympathetic, unelected judge to invalidate what the voters indirectly mandated.
It’s part of why the system is irretrievably broken and cannot be fixed as long as parties exist. Parties will always be loyal to themselves first.
The only thing that is "broken" is the part about judges usurping power unconstitutionally.