I mean, there aren't even that many "water" related champions. We have Illaoi, Fizz, Pyke, and Nami.. but three of them don't actually do anything relating to water with their abilities. Fizz summons a shark, Illaoi has a bunch of octopus tentacles, and Pyke doesn't have anything water themed to him except his lore. Nami is the only one who directly controls water with her abilities.
Are we ever going to get a carry champion who somehow uses water related abilities, or is water not a dangerous element?