It always baffles me that this is considered a luxury in the USA while in Germany (and I assume most of Europe) this is the absolute standard. Stalls where the door doesn’t lock properly or where the indicator on the outside is faded so that you can’t reliably determine if it’s occupied are already considered signs of bad maintenance. Gaps that you can look through without pressing your face right against them would be a “nope, I’ll never visit this place again” level scandal.
As someone from Europe I can guarantee you that 5-10cm (2-4") at the bottom and 30cm (12") at the top with almost no gap between the door and wall are by far enough to not suffocate. Maybe put a vent in the ceiling for good measure.