There has been consensus for some time that macOS Server has taken a back seat in the grand scheme of things and since then Apple released a guide at the beginning of summer designed to assist those to move key roles off of it as its only a matter of time before it is discontinued. I remember days when there was an actual Apple Server OS which then turned into a Server app that can be installed on top of a macOS client OS and now that will be going away. Here’s a link to the guide…check it out!