If you "just want chat" but are required to use Teams at work, you might try pidgin[1] with the MS Teams plugin[2]. The former can be installed via scoop and therefore does not require admin priveleges to install.
This thing still works, and works better than ever, with plugin for modern chat services available.
This thing still works, and works better than ever, with plugin for modern chat services available.
1: https://www.pidgin.im/
2: https://github.com/EionRobb/purple-teams