Seems to me like we're seeing something like the chicken-with-its-head-cut-off Bradley that we saw at the start of his NBA career.
He seems to get overhyped and too frantic when he moves to another, faster, more physical level of competition.
That he's not very effective as a PG is something we knew already, and some of him limitations have been exposed in the playoffs, where teams have more time to prepare for the opposition.
But it is easy to forget that he won't even turn 23 until next season. I think he has put too much pressure on himself to show he's more than a one-dimensional player. It's been reported for years now that he's a great shooter in practice, and we saw him bring that into games once he got into a rhythm last year.
By next year he'll be stronger and healthier, he'll have his shot refined going into the season, he'll settle down again--and he will no longer be asked to do more than he's capable of.