Thank you for your votes and comments on this feature. The team is in the process of finalizing designs for deleting private chat threads. I will update as we have more progress to share.
An error occurred while saving the commentBalazs Merth commented
Just as much as a failure to industrial standards, it is also a serious data leak point. My colleagues discussed financial matters in a chat after a regular meeting, now I cannot delete the messages, as they were signed in as guests. I would really appreciate even an admin right to delete unwanted messages.