I encourge accesability options, but they also have to be, accessable. Sure a lot of people can figure out how to install a font like opendyslexic, but if it isn't installed by default then it won't pop up on people's radars as easily. So they go with the best option avalible to them then.

Yes, but they're less common to be built into font packs. It depends lot person to person too what works well for them.