Does macOS Sierra support multiple users simultaneously connecting to the same machine using screensharing? Apparently this was possible with Yosemite, but I've never actually seen it in action, and I don't know if it has gone the way of Target Display and other cool features they've thrown away.
macOS Sierra still supports multiple simultaneous connected users. In the example below Sierra is running in a VM and admin is logged in. user is a remote screen sharing session from the VM host machine (10.9.5) – an iMac – and root is a remote session from a MacBook Pro (10.11.6):