Maintain Office 365 support for Server 2012 R2 or supply workaround
I believe Office 365 should maintain support for Server 2012 R2 until that operating system reaches its end of life, which isn't for another few years in 2023.
Organizations like mine have a dependence on Server 2012 R2 due to certain application needs, interoperability, support and other requirements. In our case, an entire virtual desktop shared environment which supports over 100 users relies on Server 2012 R2 which also runs Office 365 and has for a number of years with no issue.
Microsoft has decided to drop support for Office 365 on Server 2012 R2 this January, which is unacceptable; especially since this operating system is not EOL until 2023. Windows 7 support was also dropped, which I understand, as that OS is now EOL.
Support should remain for Server 2012 R2 or some way to toggle on a Server 2012 R2 "friendly" setting within Office 365/Teams to ensure its compatibility and stability through feature updates for existing customers until 2023.