Stylistic integrity makes the game vastly more fun in a quiet but crucial way by making it possible to consider the world of the game as a whole and any particular boardstate to be an expression of that world.

The world of MTG considered as a whole was a multiverse of high-fantasy-themed planes and powerful dimension-hopping wizards. Exceptions to those rules, like the futuristic expansionist biomechanical civilization of Phyrexia or the industrial ecumenopolis of Ravnica, were reacted to by both the global worldbuilding and the cards themselves. This was the worldmodel that the boardstates abstractly reflected.

Planes like Ixalan and new Kamigawa - both having excellent flavor on their own, by the way - lead to a reduction of stylistic integrity, that is now being completely destroyed by 40% of upcoming cards being from Universes Beyond and un-cards sanctioned to play outside un-sets. The worldmodel doesn't hold. Space Marines with heavy bolters march alongside Walking Dead survivors with bats and pipe bombs, going against the knights of Eldraine armed with lead pipes that are clues to a murder.

Magic needs a new worldmodel to embody and a new aesthetic to uphold.

Smash Up! is a game of dinosaurs and disco dancers going up against aliens and Brothers Grimm characters in a battle for world domination, with fairies and superspies trying to claw out a second place.

It's great, I love it. It's a kind of aesthetic and worldmodel that is possible to tie to MTG as it is currently going forward.

It's also rather hard to tell serious stories in or to make feel dramatic, because, generally, the holes in the worldmodel are patched directly via Rule of Cool and Rule of Funny.

If MTG keeps pushing it's existing-from-the-start angle of being a drama and a serious battle while having no worldmodel and aesthetic, it's gonna be totally impossible. If it's gonna do that while having SmashUp!-like worldmodel and aesthetic, it's gonna be an uphill battle that is totally possible to win I am not sure MTG writers are up for.

The only other route here is to drop the pretense of drama.

Magic('s product managers) wants to be able to do ALL THE THINGS. So yeah, we've got over-the-top genre theme parks and ramping UB stuff. I'd say more than Smash Up, it's remodeling itself into Weiss Schwarz. Which doesn't tell its own stories.