I think it has to do with a late 1990s and onward obsession with personal space and privacy and coddling in society starting in the US. The ideas of that no one should ever have to feel an ounce of discomfort anywhere.
No showering after gym class because one guy might feel uncomfortable with his body and be shamed, urinals fully divided because your ‘privates’ are a sensitive body part no one should see without emotional preparation and permission. Even at my doctor’s office recently, my urologist-the penis and testes specialist doctor, left the room for me to simply pull my jeans and underwear down and then had me around a curtain to check my sack even though we were in a private room.
It’s ludicrous and what they think they are preventing is actually developing adults with no self identity or resilience. Adults who say they are triggered by everything and young men depressed about, say for example, their penis size or chest hair because they have never seen another nude man to realize they are perfectly normal.