Before we can even think about some kind of desktop spin, there are massive infrastructural issues preventing me from using Linux as my primary machine. I run several Linux servers, so my experiences are based on my experiences running those, and my experiences stripping desktops out of Linux machines that had them when I didn't want them to.
- Sound never, ever works: Alsa, pulseaudio, pipewire...some apps require one, some apps require the other, and they don't work together at all well. Plus sound is considered part of the userland desktop environment. So if there is some problem preventing the GUI from launching and dropping me into a shell, I can forget about having any accessibility what-so-ever. We're what feels like decades away from having the advanced features that CoreAudio on mac or WASAPI on windows offer (audio ducking, first-class support for multiple soundcards and routing audio from different apps to different outputs easily, per-app volume adjustment, loopback recording, low latency, any kind of spatial anything, etc.).
- Similarly, all of systemctl's targets are set up really, really badly for accessibility. If one of the drives in fstab can't mount, even though no core services depend on it, SSH won't come up, sound won't come up, networking won't come up, meaning I have absolutely no recourse other than "get a sighted person to come to my house and fix it" because I did something as simple as swap a drive. These days, mac systems can launch a full screen reader during system recovery. Windows isn't quite as slick, but it's close; it'll do the best it can to boot and get me a screen reader, no matter how badly things are broken. Linux will just give up and die, assuming I can read the screen and type on the keyboard to fix whatever happened. I need the system to require, at least, sound support and a console screen-reader no matter what; if those things don't exist, it's the equivalent of the machine just showing a sighted person a black screen with no further info.
- The primary console screen reader, speakup, still requires a kernel module. If apt updates my kernel, it can (and does) kill the screen reader entirely.
- Linux has no comprehensive, standard, accessibility API that will work cross-window manager, cross-desktop, and cross-platform. In Windows or mac, there are clear guidelines that developers need to follow to create accessible apps. If an app is inaccessible to me, I can refer a developer to first-class, well supported and understood, API documentation telling them what they need to do in order to better interact with my screen reader. On Linux, that's not so easy, meaning apps just never get fixed, because developers working for free just can't be expected to figure it all out themselves.
Until some of these basic problems get fixed, creating a fancy new desktop spin is just walpapering over basic design issues that will keep blind folks third-class users on Linux well into the foreseeable future.