[SheinhardtWigCo]

This is the tip of the iceberg. macOS itself is very chatty. There are a ton of Apple-signed system daemons constantly phoning home.

[mightysashiman]

At some point I tried scripts aiming to disable daemons and firewall blocking MacOS stuff phoning home constantly (especially since I use no iCloud stuff) to make my system run a little leaner. But macOS is just such a complicated blackbox I just forgot about it... :(

[LoganDark]

Little Snitch works great for this if you don't mind paying a little money ($59)

[sitzkrieg]

api.smoot.apple.com is highly recommended reading

there is a couple other obnoxious ones i cannot recall right now