there’s a polite way and an impolite way to enforce copyright ownership.

the polite way is, when you learn about unacceptable copyright infringement occurring, you send a takedown request or a DMCA notice.

the impolite way is that you first post on social media that you approve of the alleged copyright infringment and advertise it as the best way to read your work, then reach out to the infringers years later telling them you’re interested in collaborating and don’t intend to enforce any legal threats, then go back on what you said and threaten a DMCA to try and rehash old internet drama from five years ago.