I have a relative who has it and he was taken the piss out of through out most of his life and mostly by his own Dad. He now lives in another Country where it took him 3 years to learn the lingo and he is doing very well in his chosen career. He found it a real challenge to learn a second language and there were times he didn't think he could do it. His kids are bilingual.
Socially he had no problems, other than mates doing what they do and taking the Michael out of each other, but you wouldn't have known, because we never saw him write anything.
I also think that as was already mentioned, there are different levels of dyslexia and some have difficulty with number recognition as well as letter and train yourself as much as you like you will slip up now and again. It also depends on the support and education that they have had, as many older people didn't get any support at all at School, so for the older generation it was a matter of just 'dealing' with it.
Spell check only works if you can recognise what you are looking at is correct.