Wow. Indeed. That solution is pretty slick to have. This allows us to have a completely GAFAM free solution in terms of corporate communication. \o/
And in order to respect new privacy related regulations like GDPR, it really comes in handy. Especially as you know that some local European govs are beginning to become suspicious towards solutions like Office 365 which is not respecting GDPR.
Plus the fact that the EU court invalidated the privacy shield recently which means using US cloud is incompatible with EU privacy law.