I have to basically agree with this. While in theory, the gender-neutral
restroom could just be labeled "restroom", people tend to expect
restrooms to be segregated by gender, and will probably be confused if
it isn't explicitly specified that this particular one is not. 

{Hoch} is probably fine if you're making each sign only one word, but
you might need to do something like {Hoch nuv puchpa'} if you want to
include the "restroom" word, to avoid that "all restrooms"
interpretation. 

If I needed a restroom and saw a door labeled Restroom, I wouldn't be confused. I'd go in.

On the other hand, if I needed a restroom and saw a door labeled Everyone, I wouldn't be sure what it was trying to tell me.

-- 
SuStel
http://trimboli.name