I recently asked a meta question which linked to several site proposals. One of those proposals was deleted and the meta question was also marked deleted by the Community user. Was this automatic as a consequence of the linked site being deleted?
Even without that linked site, I think the meta question is still valid and still useful for discussion.
If this auto-deletion is part of the algorithm, it provides strong incentives for people to not provide links to proposals which might be deleted in the future, during meta discussions.