You can disable Chat for Teams users, but is this a good idea? Chat is an integral part of Teams and disabling it seems like a bad idea for many reasons, not least being compliance as all you’ll do is drive users to find another way to communicate – like WhatsApp.
Microsoft is raising the limit for Teams meetings and group chats to 350 participants. The group chat limit was increased to 250 in early May. The new increase is temporary and Microsoft will review it in September to decide whether to keep it at 350. The update is already rolling out and should be available worldwide in mid June.