Rui Carmo
The writing’s been on the wall for a while, but it’s still sad to see some of these go away, especially because (for calendaring, for instance, or sharing contacts) the client-side apps are similarly neglected and only talk to public cloud services or (poorly) with Microsoft Exchange.
Most of these are trivial to set up on a Raspberry Pi if you really need them–but since Apple never got around to do the most basic of shared cloud services properly (even photo sharing is still a mess), not many people are likely to miss them.