Now in public preview: Swap content with gallery during meeting

Jin Chen thank you for your feedback. Yes, to use this feature, some user needs to share content (like Desktop) and some participants need to have their videos on. This feature was initially available in Public Preview only. To access it, your organization needed to enable Public Preview for you (Public preview in Microsoft Teams - Microsoft Teams | Microsoft Docs). Recently, the feature has become generally available and there is no need to be in Public Preview to access it. (If you have production EDU tenant, this feature requires Dynamic View. Roll out for this feature has just started, too.) 

I think EDU tenants still do not have Dynamic View, and a whole host of functionality like this appears to be dependent.  So you can't say "Everyone"...