I actually saw those once! Was so confused what they were at first, I was visiting the USA at the time and they had them in some of their public toilets.
But then they also have a huge - intentional - gap in the doors on those cubicles, so that people outside the cubicle waiting to use it were just watching me poop.
It was really fucked up, and not just a one off design mistake, this was EVERY public bathroom. Mental.