Skype for Business, Lync, and in the dark ages Office Communicator even had it. If you left IM open and your PC unlocked but you weren't using it, after a user set delay your status would turn to idle. You can't set the timeout in Teams anymore, IIRC.
Does Slack not have this? I'm 99% sure Zoom does as well.
I admined slack long long before it had any Enterprise bolts so I'm sure it has stuff like that now. Teams makes it front and center so you can track your employees interactions and chats, calls (not emails like I thought).
Does Slack not have this? I'm 99% sure Zoom does as well.