History

Workplace conditions definitely factor into it, and workplace saunas were decidedly not a thing in West Germany. But the entire concept is built on an idea of nudity being no big deal in appropriate contexts that was not specific to the DDR, but has existed in European culture since the naturalist movements in the earliest days of the 20th century, a movement that was largely normalized in both German cultures by the 1970s. It always had more traction in the DDR, and that may have indeed been due to the less performative, less perfectionist, less stressful culture that arose under AES material conditions, but we should not forget that America is just extremely fucked up about nudity. To the point that even West Germans have always joked about the American double standard of being super prudish about boobs while having no problem with the most egregious displays of violence.