Allowing deletion of private chat threads is on the backlog.
665 votesFiona Perry commented
When not all colleagues are able to attend a Teams meeting we record it so that they can catch up later. The meeting recording can easily be shared after the meeting, but the chat is only open to those who attended. Being able to export the chat to accompany the meeting recording would be very useful.
This feature item is still in the works. We will keep you posted as we have new info from the feature team.