This seems like a surefire way to build a private echo chamber. I doubt a simulated audience is going to challenge your thoughts or help find what you are trying to say.
Do the commenters reply to things now? It might be nice to have personas that usually reply, others that reply rarely, etc, and that way you might get long discussion chains, or drive-by comments, or anything in between.
Public social networks are already building echo chambers. At least this one could be made to not have supremacist spam all over it like Twitter/X. Is it really any worse? I guess it wouldn’t have real life impact with an audience of humans.