Those stories are amazing! It really seems to suggest the existence of a soul or astral body, something that isn't bound by physical limitations. A lot of people think that OBE/AP is just a really vivid type of lucid dream, and therefore all imagined by the mind. Yet it seems highly unlikely that a mind that has never seen could just suddenly "dream" what it is like to have sight. It seems more likely that people are spiritual beings experiencing temporary physical limitations.
Also, if you believe in reincarnation, it makes sense that a congenitally blind person would see in the astral. It is unlikely that his or her astral body is also blind because that would suggest that he or she has also been born blind in every past life, which would just be really really weird.
One should also keep in mind that sighted people often find themselves blind or with limited vision when they first project, so just because blind people don't always see while projecting doesn't necessarily mean that it isn't possible.
Also, if you believe in reincarnation, it makes sense that a congenitally blind person would see in the astral. It is unlikely that his or her astral body is also blind because that would suggest that he or she has also been born blind in every past life, which would just be really really weird.
One should also keep in mind that sighted people often find themselves blind or with limited vision when they first project, so just because blind people don't always see while projecting doesn't necessarily mean that it isn't possible.