I dislike the wording “by the creator” and “message from the creator:” as they are toxic parasocial relationship inducers.
While that sort of wording is benign to an adult, a child will take it literally as “the owner of this group has PERSONALLY banned you, they hate you, they are now your sworn enemy”.
It is essential for digital civility and developer safety that internet anger does not get directed toward specific individuals, it instead should be redirected towards a company, entity or object.
I will not be using this API until the wording on the ban message is amended.