"all Microsoft licenses will be terminated"

Ok, and what will be the alternative? I am not talking about the easy part, like documents creation, although I don't see walking away from Excel as LibreOffice alternative is a bit of disappointment. But what about the whole security/networking/permissions area? What is the viable alternative that can scale?

Remember Covid times? In Poland all schools got access to Office 365 (overnight ) and education kept going. 500 000 teachers and a few millions of pupils. Tell me who else except Microsoft or Google have ability to support that?

In my part of Germany we used BigBlueButton after a short time when Zoom was used. E-Mail and a LDAP account was also always available for students. It's not exactly Rocket Science.

There are also ready made solutions available for purchase

https://www.univention.com/industries/educational-sector/

99% of users, could just as well use another form of spreadsheet. Only complex macros or custom integration does. Perhaps very large spreadsheets, I don't know.

Also the IT Administrators that may be skilled in Windows Server and similar but less so in Linux. Thats something that beeds to be taken into account. Can be changed they can learn new things, but that takes time.