This request is still on the backlog.
Teams is already threaded! Just make sure to use the “Reply” button instead of the bottom compose bar when responding to someone’s previous post. That will thread the conversation.
We have been iterating on different designs and are starting to test internally. I don’t have a timeframe but will keep you posted.
This feature request is still in the works. No additional updates are available at this time. I’ll keep you posted as I hear more.