Yes. Even tho in my family we're very careful to knock, my brothers weren't shy. They worked out a ton and took good care of themselves so they felt extremely proud of their bodies. They never closed their doors if they were naked. Walking back from the shower they sometimes didn't bother putting clothes on. We got used to it pretty quick and it stopped being a big deal.
Me and my sisters were the opposite. No one ever say saw naked by accident, even each other. Seeing each other nude on purpose, is another story.