I’ve been on Bluesky since February. I have yet to see any nudity that I didn’t actively seek out. It’s not too difficult.
I’m on a (streams) instance on which someone else is following pr0n accounts. That instance is small enough (13 channels, including clones of external channels) to suggest them as contacts to me until I’ve removed them as suggestions.
Only boobs I saw without searching mastodon.social for non-pr0n hashtags.