Are you watching the right game? Bairstow hasn't gone into his shell, he's playing well away from the body throwing his bottom hand through the ball like he does in ODI's. The only difference is that with a red ball that moves, trying to play that way and smash everything isn't a smart technique. If I was a selector I'd look at dropping him as he's averaging just 30 in Tests since he stepped up to open in ODI's which isn't good enough for a middle order bat.
I'd love to see a team of: Burns, Sibley, Hain/Denly, Root, Roy, Stokes, Buttler/Foakes(WK), Woakes/Curran, Ali/Leach, Archer/Wood/Stone, Anderson/Broad.