Percy, first those are some lovely pictures mate.

Guys, I'll just measure it to put the issue to bed. I have a 77W flight today in J and will hopefully remember during my next (so far unscheduled) 33G flight.

I notice the difference in space most when you raise the aisle protector thing (it is raised in your 333 photo, but not 77W photo). I'm confident you'll notice the difference when that's up. Your elbows won't be impacting it like they are on the 333. I also sometimes sleep on my side with one of my hands under my head, and i notice it there. That said, it is possible the only difference in seat space is at the shoulder area.

Another way to think about that aisle protector space between seat and aisle is just think of a triangle. That space is indeed a triangle between seat and aisle. We all agree the angle of seats face more north/south on the 333 vs 777. Ergo, at a minimum that aisle protector (aka shoulder) space must be bigger on 77W....