This is probably one of the best yet most underrated features of the various stock Apple organizational apps: they work just as well as vendor agnostic clients for standard protocols (IMAP, CalDAV, CardDAV, etc) with relatively little favoring of first-party services.

I wish this were more common, but instead it’s more typical to see things like the vendor agnostic Windows Mail being abandoned for “new” Outlook which is much pushier about using MS services.