There’s little point in having a private community if it’s not exclusive.
You lose all the benefits of an open community, without the gains in intimacy, privacy, and sense of belonging.
Exclusivity means members are either invited or have to apply. It also means you reject the majority of applicants (people soon realise when everyone is accepted).
Exclusivity means there is a barrier applicants have to cross (skill acquired, experience gained, track-record established, contributions made, relationships nurtured, payment processed etc…) to be one of the whole group.
The purpose of having a private community (or area of the community) is to enable members to share information which might harm them if made public, create a sense of belonging, or ensure a high standard of contributions.
If your private community isn’t doing that, why make it private at all?