I disagree. The 789 2x2x2 config is much more spacious than the 77W's 1x2x1. And while I haven't flown the 1x2x1 config on the 789/781, it can only be worse, as the 787 is a much narrower aircraft.

The 2x2x2 configuration gets a knock because only 2/3 of the seats have aisle access, but (a) that's still the majority of the seats, and (b) how important is it on a mid-con anyway?

I don't see any advantage to flying further in a less-roomy config.