By chance, don't you know why we cannot have electric wheelchair for everyone who needs it? Manual wheelchair seems to be not very convenient and to require lot of effort to use it.
we barely supply good manual wheelchairs to everyone who needs them, the article talks about why not.
Motorized wheelchairs are not a good fit for everyone. They are much bigger, heavier, harder to transport (you need a van), and even with a clutch to allow emergency non-motorized use, because of their design and weight, they can't be really used without a motor, so you're f*ked if the battery runs out.
They're good for some uses, for some folks, but are not a solution for all.