I have never used a shower door in my life. They are always reserved for the Master Bedroom, never the guests'. Guess that "open air" would mean nothing to block the water. That doesn't sound tidy enough to be used unless you needed to pressure wash your bathroom. While bathing "skinny dip-style" sounds freeing and refreshing, no one has ever taken me to a lake.
I used to use a tub to bathe. No, not a bath tub. It use one of those small ones that hospital patients relieve themselves in. But don't worry, for this was was new (or at lest sterilized). My fondness toward that method wasn't great;it took forever relied on boiling water on a stove. I did this for ~8 years before I moved somewhere with proper plumbing.
And, yes, I do shower/bathe, but only with a curtain.