Greetings!
Well, I typically run harsh, brutal worlds where handicapped people in an adventuring team simply are not going to fit in well, generally speaking. As far as that goes, 98-lb weaklings aren't likely to make it, either. Everyone on a team is assumed to be mobile, independent, and functional, capable of dealing reasonably well with most physical obstacles and environments. A Wizard that can't swim or climb a rope is likely to be sent back and searches done until the party finds a Wizard that can swim and climb a rope. No one gets carried anywhere.
Most people don't have access to special labs and uber magic super hero gear, doodads, and technology.
Severely handicapped characters don't fit well into the games I run. They likely get retired to a town somewhere, and a new character is rolled up. That's the breaks.
Absent a whole super-industry of magic and technology to *make* such handicapped characters otherwise functional and allegedly not a liability--it re-orientates the team's focus on how to constantly accommodate and deal with the handicapped character's problems and limitations--instead of getting on with the mission, and jumping crazily into adventure. I don't see that as a positive dynamic, and I don't think most players at the table would be overjoyed about it either. A character having a weird, glass eye, or a metal claw hand, is one thing. More severe handicaps become more problematic, and are generally dealt with as I mentioned.
If you like superhero blind characters, or characters confined to a wheelchair, or quadriplegics, great. In my world if they weren't safely locked away in a town somewhere, they would be eaten, or otherwise swiftly killed.
Semper Fidelis,
SHARK