on the upside, you can make a .mobileconfig that disables most of the apple cloud service shit for macOS, like music/icloud/appstore/etc. here's one:
https://git.eeqj.de/sneak/pub/src/branch/master/sneak/disable-apple-apps.mobileconfig
you can't configure IMAP email on macOS mail any longer without it phoning home to apple when you do so. i haven't inspected the traffic or binaries that do so, but if you want to configure imap email manually (or import a profile that does so) while blocking all communication to apple/icloud servers, macOS Mail.app won't work.
(edit: it works when installing via a profile, but only after some timeout/delay.)
remember when computers were embedded machines and the interface latencies were below the boundaries of meaningful human perception?
remember how that all got fucked over the last few decades?
there are some (not all, but some) operations on the new rMBP that feel that electronic lightspeed instantaneous. i'm not sure if it's the 120hz display or the stupid fast cpu or specific macOS optimizations, but there is a man-machine tight feedback loop of the kind long gone. it's spooky.
one of the best videos on youtube:
Hacker, researcher, entrepreneur. Make sure we're connected at https://sneak.berlin/list
these toots are also available at https://s.sneak.berlin/@sneak.rss if you're into that.