1.) We don't like your poster so you better remove it or we'll badmouth you within our network.
2.) You have 1 day to comply.
3.) You can instead work with an artist we will recommend (aka connected to us), and we'll cease.
Textbook mafia-style extortion.
However, I’m just pointing out that as far as the implications of the threat goes, in most instances it would’ve just happened anyway, without a “warning”, because people simply post things to make fun of them and mock them. Sometimes those accounts might at least anonymize their subjects, but this might be a name them and shame them type situation.