Agreed and adding +1 about permissioning. Since comments are not exposed as a database, we cant limit who can or can not see the related comments.
“UI will be quite bad, unintuitive, etc. And you will not gain much having comment as a database. BTW, what exactly you need?”
What if you set create a “tread view” which is showing entities but in a thread view like comments, but in reality they are just entities, not comments under the hood?