This is literally the first modern internet meme, but you can avoid that unfortunate effect by first setting a leaf-thin layer of toilet paper on top of the water.
But often I just really want to poop right away :)
Are you familiar with the paper napkins rolled up so tight they look like a peppermint, and when they get wet they unfurl? Maybe American toilets should have a jar of those things next to it on a shelf so you can quickly drop one in and go on with your business :)
For extra vintage meme, they should be shaped like sea shells.