In 2018 Apple announced it would turn off Back to My Mac on July 1, 2019 for all versions of macOS. That day has arrived.
Back to My Mac
Apple is Shutting Down Back to My Mac on July 1
On July 1, 2019 Apple plans to shut down its Back to My Mac service. This let users set up a network of Macs that could be accessed remotely.
Facebook's iPhone Activity Tracking, Apple Kills Back to My Mac - TMO Daily Observations 2018-08-23
Andrew Orr and Bryan Chaffin join Jeff Gamet to share their thoughts Facebook using its Onavo VPN app to track iPhone user’s activity, plus they speculate on why Apple killed Back to My Mac in macOS Mojave.