Still relevant? Especially when it comes to building and using Xwayland.
Building xserver master with the xwayland depencies installed (or force --enable-xwayland) will build xwayland with the xserver.
But you need the compositor to have adapted to the recent changes in the way to handle xwayland, so wait the patches for it are merged
I'm waiting for WaylandX... for running Wayland apps on X.
I IMHO do not see any reason to comment this Michael's info. Let developers do their best and let us wait for June news.