I have read this only now and don’t care enough about celebrities to delve deeper than this article.
Nothing in there sounds problematic to me. Dude expressed his boundaries (as in, non negotiable dealbreakers) and that’s okay. Of course it is gonna sound like an ultimatum if it is an ultimatum, why is that not okay? Why can a person not say "stop doing this or we can’t be together any more"? If it were something else than posting bikini pictures, for example an onlyfans account, is that enough to be a dealbreaker?
I wouldn’t want such a person as a partner myself either, regardless of how insignificant or petty the boundary is it should be respected and if that isn’t possible, move on.