The list is generally correct but these days, systemd has made quite an impact also. If a distribution uses systemd, it has one software to handle everything from booting (instead of grub), handling start and status of all system services etc. Its probably the largest change to the Linux ecosystem in a long time.
X11 and Wayland are desktop protocols, so things like desktop environments and window managers depends on one or them to be installed. Without them, you don’t get any graphics except for the console. It’s all built on top of one of those.