Oh yeah, replacing AWS may be easier than replacing O365... or otherway around? My company also went all in for O365. It's about replacing Mail, Teams, Teamwebsites, OneNotes and for sure so much more... We also ship our patches via Teamwebsite, it sounds stupid but well, it works... And talking to costumers when they still have Teams but your company ditched it, how would that work and so on... You have to have a lot of hope to think that all this will or can be replaced in the near future.