Or when they switched from applications requesting exclusive access to ALSA audio devices to using sound servers for mixing, or when Xorg autoconfiguration was introduced (obviating manual Xorg.conf creation), or when the modesetting DDX replaced vendor specific DDX packages, or when Wayland was introduced with full backward compatibility with Xorg via XWayland. I suppose that last one is more of a lack of change.

> when Wayland was introduced with full backward compatibility with Xorg

you shouldn't believe everything you read on the internet.