SUSE used Teams for years (particularly under Melissa Di Donato, who made everyone use it). I used to participate in some of the community project meetings that wound up being on Teams because it was the approved solution they could use. It was the reason why the openSUSE Project deployed a Jitsi instance.

They do not use Microsoft 365 or Microsoft Teams anymore. They use Google Workspace just like everyone else now (the mail headers tell you that). I don't know anything about their workflows, though.