Microsoft is finally adding end-to-end encryption support to Microsoft Teams later this year. A preview of end-to-end encryption in Teams will be available in the first half of this year for commercial customers. It will be available for 1:1 unscheduled Teams calls and is designed for more sensitive conversations.
This will mostly be useful for confidential conversations between employees or for scenarios like an IT admin providing an employee their password over a call. The initial preview will be limited to 1:1 unscheduled calls, but Microsoft plans to expand this to scheduled calls and online meetings over time.