Teams users can now see read receipts for messages in private and group chats. The read receipt is a visual indication that someone has read a message rather than a positive signal back to the user, but it works well. Controls over read receipts are available at a user and tenant level (through messaging policies).
Teams personal chats display an activity tab that allows you to get an insight into what person you’re chatting with is doing. Some might worry that the other person will see something that they shouldn’t, but there’s nothing to worry about.