I think there is a lot that the author is right about.
However, removing X11 season was a decision of the Gnome Team not the Ubuntu team and I completely respect this.
Yes you can keep shipping it with the X11 optio, but someone has to maintain it. The gnome project has only limited resource so it's either removed or an unstable mess... removing in this case is always the better option IMHO.
I think the core takeaways from all this is, we (as a community) should definitely no longer recommend Ubuntu as the default distro for newcomer to the Linux world.
How does anyone come to the idea to built a tool to be used in a federated context and hardcode into it which instances are not allowed to be used with it?
However, this is just one person. Maybe the Dev did not expected anyone else to use it and just but the blacklist into it for personal reasons...