My worst experience is likely been fixed/demolished long ago, but likely points to the right answer for “in the world”.
In 1992, I spent 3 months in Germany. Germany had just re-united and I was able to drive to Berlin on the A 9. It wasn’t the most picturesque drive I took, but it was memorable. The road had just opened and still had giant craters in it from WW2 every now and then and a recently abandoned fortified border.
Then there was the rest stop I ended up at.
It was all concrete and really big. It was very obviously an original issue rest stop from the 1930s. There were big eagles cast into the building and some empty places where something had been blasted off the building
The bathroom was the horror show. It was a beat up tiled room. One side was sinks, the other was a row of poles. When you got to the poles, you could see that there was a pair of poles on either side of two cast iron foot shaped rises in a cast iron thing that had a hole between the poles. You were supposed to grab the poles, put a foot on each foot print thing and drop a deuce down the hole. There were no doors, walls or any other way to get privacy. And no TP either, so the poles didn’t really look clean at all.
Now, I’m sure that this rest-stop has been destroyed and replaced with a place that charges 5 euros to crap in a luxury poop palace since 1992.
HOWEVER… I would bet there are areas of Eastern Europe or Russia or the like that still have the poles and the holes.
PS, found a picture of a squat toilet. Image this.. but cast iron, rusty and public.