Hi @eslachance, welcome to the GitHub Community!
If you have write permissions to a repository, you can hide, edit, or delete comments by using the tools described here:
Additionally, users with admin permissions in a repository can permanently delete an issue from a repository by following these instructions:
Unfortunately, there is no way to turn off commenting on a gist. May I suggest that in order to maintain the comments on a gist, you re-create it as a secret gist. That way you can control who has access moving forward.
The best place to submit feature requests and share more details about your use case is through our official product feedback form so that our product team can track your request.
I hope this helps!