Or just swim about in circles, as was the case with one of my kitties (who fell in of his own accord).
funny how knowing we’d do better by staying calm we’ll rather panic anyway. or maybe we just lack those baby fat to stay afloat 
Adult humans can’t swim because of the way we have learned to walk. Almost any other animal, and human infants, can make headway through water simply by going through normal walking movements. Some dogs for example never learn to swim, and instead try to climb up onto the water surface. But this still allows them to move effectively. This ability is aided because animals will float pretty much the same was as they sand, that is legs down. A sight tilt of the neck enables them to breathe.
Adult humans have a problem. We tend to float face down, but we walk legs down and head up. As a result we try to keep our heads out of the water to breathe, but when we try to walk our movements drive our heads under. Bipedal motion just doesn’t cut it under water. This results in panic. In order to swim humans need to revert to an infantile crawling motion, and this doesn’t come naturally.
Several of my current cats, and previous ones (I only have three, currently) love water. My youngest, Alex, jumps in the tub with me when I take a shower, and rolls in the water. Foof, our eldest, likes water ran in the sink for him.
My guess, besides the most obvious which have already been stated, would be that cats don’t see up close very well… and water is hard to smell… so when they get touched by it, it’s a shock. But, that’s probably one of the smaller reasons for the general dislike of water.
Blake ooh, that makes sense. the natural reaction would be to stand…
back to the OP i think for a cat wet fur would really be a chore to groom lick by lick…
I had a Maine Coon that loved water. Rain, baths, squirt guns, he loved it.
I never had a chance to get him in a swimming pool or Crafter Mans disposa-cat lake. I’m sure he would have loved it though.
Come to think of it. I have a swimming pool at my new house.
I have a cat.
scratches head
Hmmmmmmmm?