Squat toilets?
 

It might be quite a taboo in the U.S. or other developed countries, and even here in Brazil they're quite controversial due to their most frequent usage in prisons due to safety concerns. They're also not so user-friendly for disableds and the elderly, even though there are some relatively cheap ways to overcome this issue. On the other hand, the lower water consumption and the easier cleaning might turn a squat toilet into a more sustainable option.

The impossibility to install one in an apartment :D

And believe it or not, direct contact of sewage with the soil has been outlawed here due to contamination concerns. Septic tanks are now mandatory in areas not served by sewage treatment.

Great, flashbacks I don't need. Like the porta-s that got used as squats.

For public toilets? Sure. I think it's a decent idea...could just hose the place down a couple of times a days. Place would stay cleaner than the ones we have now.

Honestly, I don't want to come in contact with the truly public toilets out there. I'd rather hover, if I absolutely had to, which amounts to the same as squatting. Heck, squatting would probably be easier.

I had to get out my copy to remind myself of the author of The Bathroom, Alexander Kira. From a review of the three major appliances in Treehugger, https://www.treehugger.com/bathroom-...-plumbing.html

https://media.treehugger.com/assets/...ira-toilet.jpg

This work was done in 1966. Recently, a 'butt-load' of money was made with the Squatty Potty, which draws on this research.

https://www.squattypotty.com/

I started describing the results of local nationals using our bathrooms.

I did not need that trip down Memory Lane and you guys did not need a guest pass.

Considering that even some privately-owned toilets accessible to the public are often dirty and in a state of disrepair, that would be another advantage for squat toilets. Another aspect that is quite critical in public toilets back here is the high incidence of vandalism, which squat toilets tend to be more resistent to.

How wheelchair friendly are they?

Squat toilets are not wheelchair-friendly to any extent, unless provided with a seating adapter (which are commercially available, mostly in Asian countries), but neither is a regular public toilet cubicle which doesn't have enough space for a wheelchair user to transfer from the chair to the toilet and also doesn't have those support bars.