Highly doubt it, maybe a small organisation which would make sense by your comments.
Outlooks feature list is huuge. Large list of functions in Calendering alone is unmatched.
most of these things are dying out.
Bollocks.
The API is the backbone for large organisations that extends that large amount of Outlook functions beyond 365 limited services. That is being cut off in an anticompetitive move by Microsoft. It allows for information management and automation to be verified by people with simplicity and a familiar UX.