Land animals are land fish. You can not evolve out of a clade, therefore all land creatures are cladistically a type of fish, as well as land animals that became water animals again.

I'm a fish, you're a fish, we're all fish. And worms!

If the subset of cladists that don't think that's true have a problem with it they should reconsider whether they actually like cladistics, because they're rejecting evolution to deny it and embracing vibe based classification which kind of defeats the whole point.

But, of course, that's the thing with clades, it's all relative. Yes, we're all fish/worms, but generally speaking when someone's talking about fish vs whales you know they're talking about those loser fish who never left the ocean vs the land chads who went back to the ocean solely to bully them because the distinction is useful.