Re: Mir -> Wayland then?
My understanding is that Wayland wasn't "designed NOT to work over a network", but simply that Wayland was designed to handle local display only. All manner of remoting capabilities can be provided, if necessary, by an external component. Which doesn't currently exist and which nobody appears to be working on. (Other than VNC and the other loosely-coupled solutions wich already exist for remote display.)
I agree it's an annoyance, simply because when running Wayland and I'm ssh'd in to my filesever, I can't type "sudo gparted" or "sudo meld" and have the application show up on my local screen, something I've gotten used to doing while running Xorg because the X11 proxying Just Works™.
I'm not entirely sure that particular annoyance is a big enough complaint about Wayland to make it a bad thing, and in fact I'm quite sure it's a much smaller problem than a lot of the legacy features I had to unlearn when they were stolen by Gnome3/Shell or newer Nautilus versions. Then again, I'm also still running Xorg on my main systems because I use (older) Nvidia cards with the proprietary drivers, so it's not an issue I've had to face yet.