I, for one, could give two flying eagles whether or not it’s constitutional (and don’t know enough to have an opinion on that). It clearly breaks Democracy, and so is morally and philosophically wrong.
Furthermore, if legislators are going to play hardball in the open with this sort of thing, then we clearly need legislation to shut that shit down.
Bottom line “I’m drawing a map to ensure that my party gets 77% of the representation in the house while only receiving 53% of the vote” is evil-villain level, anti-Democratic scheming, and we should all be against it on principal.