bulgarian bathrooms are a bit like that except instead of filling them (which would be ineffective long term) they often have these things called "хигеничен душ" (hygiene shower) which are like a gun-style hose attachment that shoots a jet. the bathrooms are generally floor to ceiling tiled, and you can just get this thing and blast every dirty thing in the room with a fairly high velocity jet, and done. wee is no problem in the face of a high pressure stream of water, and if you don't let the solids get dry, it will remove them well also.

i've also seen those robo-toilets, first saw one in like 1998 in canberra, they have a series of nozzels that blast steaming hot water from several directions to clean down all the walls and surfaces. this also works, but is more complex and failure prone.

my ideal would be the bulgarian style butt-gun but it's calibrated to be a nice warm 45'C or so, and instead of a cheap, low coherence jet, it has a pressure vessel with an inline heater on the out-side that fills with air, and then pumps in high pressure air so it is a lot higher pressure than the mains, and will run for about 2 minutes before the water is all expelled, and what comes out is perfectly temperature. 40-45 is exactly the right temp where it melts most solid oils (tallow, lard, cacao butter, etc) but isn't hot enough to make the protein congeal. make the shape of the jet instead of a laser linear, a narrow fan, and you can just point it at the far wall, and "sweep" it down, and the same on everything, the bathtub, the shower, the toilet itself.

that's elaborate, but the bulgarian butt gun is fine especially if you use it to clean up immediately mess is made. the tiled walls mean no problem with causing damage to paint or plaster or concrete or wood, and everything is clean.