I don't know how Bradley or any other player can limit Wade defensively, especially when he settles into his groove. He is practically a player that can play 1-on-5 (although you have got to say this is hardly efficient at all), so, I can't see him getting bothered by Bradley that much.
I'll just leave this right here:
I just prefer not to base my opinions on single possessions.
That would mean Roy Hibbert is a terrible defensive player as Durant posterized him this season. Or Timofey Mozgov. Or Serge Ibaka.
Just as in those cases, that's just a weak-side block from an unknown kid for Wade. It's not as if he would allow Bradley to do it over and over again.
On the other hand, Wade scoring 30 over Bradley won't automatically make him an awful defender in my eyes, either. I'm trying to see the whole picture.