Outside of Toadette(who was just mad she didn't get big milkers, and she doesn't really want to turn back either) does anyone actually want to reverse the effect of the super crown explosion?
Hard to say, since we haven't actually seen a lot of opinions yet.
Kamek isn't interested because it reversed all that aging, and that means more time to study magic.
King and Queen Boo and Booette seem kind of ambivalent.
Lakitu doesn't seem to care, and Jugem doesn't have a choice.
Chompy just want to be with her friends, and Junior just wants to be like mom.
Outside of them (and Toadette),I don't think we've seen anyone really express an opinion about it. (The paratroopas don't seem too keen, but I suspect that has more to do with having to relearn how to fly than anything else)