This website contains age-restricted materials including nudity and explicit depictions of sexual activity.
By entering, you affirm that you are at least 18 years of age or the age of majority in the jurisdiction you are accessing the website from and you consent to viewing sexually explicit content.
You need to explain why because either they’re misunderstanding something or the two of you are using different definitions of private. In both scenarios asserting that something isn’t private won’t do any good.
As you wish, and probably a good idea;
Voting on lemmy is not private because anyone who wants to find out. Can. Be it moderators, adminis, or users on federated sites that simply show it for everyone.