In a context of 787 when compared to A350 is there any meaning, any significance, in asking whether the innovations of the 787 make some difference in the long run? Wasn't the use of composite structures much more extensive in the design than in anything previous? And the passenger cabin a more comfortable environment?
I recall a one-off report in AW&ST in early 1976 entitled "Aerospace Materials" which contained extensive reporting about composite materials, then presumably less advanced than at the time the 787 design was completed. If the level of innovation present in the Dreamliner is not significant, I'm ready to plead biased memory.
Of course the production glitches and the deeper problems they reveal or at least suggest aren't reduced or minimized by the designers having innovated to get there.