> it cannot be controlled with dbus, sway/i3-IPC or other technology. The reason for this is that we believe that custom IPCs and protocols create a fragmentation that hinders general Wayland adoption.
If anything, this leads to more fragmentation since now you have to hack your own way to control it, rather than using something standard (at least on Linux) like dbus.
You can only really do that by forking though, so it's probably not going to happen. That said, the unspoken part of that is that it supports Wayland protocols for the features that would be provided by dbus/swaysock/etc. so you can just use "stock" tools like wlr-randr and sfwbar to manage outputs or provide a task switcher. Some of these protocols are still wlroots extensions (though that doesn't mean you won't find them supported elsewhere) but increasingly those are being replaced with standard protocols (with the caveat that GNOME Mutter will probably never implement any of them, but I'm not sure if anyone cares; GNOME is probably going to wind up just being it's own thing that is technically Wayland but not how anyone else does it.)
(P.S.: I suspect Swaysock might've never existed if it were not for the fact that Sway is more or less a direct recreation of i3wm as a Wayland compositor; it is the equivalent of i3 IPC. You can and should just use Wayland protocols even in Sway where possible.)
The wlroots extensions are one attempt at creating such a standard, being used by pretty much all compositors except for KDE and Gnome. The issue with that is of course that all wlroots compositors combined have a tiny market share compared to either.
DBus is just an RPC layer. You still need to define a standard DBus interface for any given feature. Not all UNIX-likes ship DBus in the base system (which is certainly one component of why Sway has Swaysock.)
Meanwhile, every Wayland compositor speaks at least the core Wayland protocols and probably some of the extensions, and they all go through the same standardization process, whereas there's certainly no such process for DBus or random UNIX domain sockets based protocols. It's simpler to just use Wayland protocols where possible.
If anything, this leads to more fragmentation since now you have to hack your own way to control it, rather than using something standard (at least on Linux) like dbus.