To call him an impact player is nonsensical? I'm confused.
KDB is, yes. Özil has a different level of intelligence which separates him from James, despite having less goals, though as a #10 there's little between them and I said in 14/15 James and Özil were by far the best two #10s in the world, and well on Özil's form last season yeah, there's probably still not much at all between him and James. Özil has the same problem, though, he is ineffective at this point in his career as a wide playmaker.
Isco is, like James, not particularly explosive or athletic, but he's a superior footballer...Isco is as pure a footballer as we've seen since Cazorla, or the closest thing to an Iniesta type in modern football.
Isco too was on the border of falling out with Zidane too, for the same reasons as James, but was the better/more effective player, and thus didn't. Basically Isco won the battle for a place, not the other way around, that Zidane had something against James and not Isco.