Always remember this highly relevant paragraph from the Charter of Fundamental Rights of the European Union:
"Everyone has the right to freedom of thought, conscience and religion. This right includes freedom to change religion or belief and freedom, either alone or in community with others and in public or in private, to manifest religion or belief, in worship, teaching, practice and observance."
Note that this legal all-encompassing statement includes the phrase "freedom of thought..., in public or in private, to manifest... practice and observance." I feel that about covers: "I think being naked is a harmless activity and anyone can choose to be naked, in any context, without fear of censure."
Regardless of whether being clothed at any particular time is sensible (fire-fighting, etc.), or necessary (climbing 8,000 meter peaks, etc.), or useful (active military operation behind enemy lines, etc.), or chosen (I feel like being dressed today, etc.) The important point is the activation of choice.