as someone that needed input assistance for some time, i totally feel this. people always assume accesibility is just for visual impaired users and lots of other visibilities are usually sidelined or completely ignored (not that visual impaired users get proper support either but they get way more attention). there are also so few options that most users (specially non technical users) are forced to go with whatever setup can support them, regardless on how hard it it to setup. i still remember that back in the day the best way of getting voice input support was to run a windows vm to run dragon language processing (name forgotten) and then making some tech wizardry to pass the commands back. at least having something running natively, even if it's proprietary is an imprevement.
the biggest challenge and also the biggest benefits i got where from moving all my setup to a keyboard centric one (tiling window manager, mostly terminal applications for everything, keyboard centric browsers) so i could not use almost any of the popular programs. When I was forced to move to voice input, i used numen (foss and quite small) to emulate the keyboard so i needed no integration with anything, just do the exact same keypresses but with the voice. since i didn't need a pointer often, i was able to get away with head tracking that was activated by a voice command. it was very uncomfortable but i didn't need it often enough to require something better
at the end i had to almost craft a complete system and limit my computer usage to a very minimal subset of possible applications. i was able to prepare for a long time (learning all the tools, learning enough to modify others or write my own) so it was not that bad but i doubt it would be even an acceptable experience for anyone that doesn't have a computer thinkering hobby. the pust to wayland will throw many people under the bus but hopefully there will be enough noise now that there will be soon better alternatives