The good news I think is that you have to be really really specialist for the specialist knowledge to actually be the important bit; for most it's the ability to obtain specialist knowledge, and apply it.

As long as we can adapt, move on to the next knowledge-needed area, we'll hopefully be alright.

(I think there are many analogies here to things people have always said about undergraduate study – e.g. it's about teaching you to learn, not teaching you the specific things you're taught, to be remembered and applied forever.)