Seems as if the plan by the seat designer is not to get carriers to have every row in this style but to have just a few rows at the back.
If, on short haul, they replaced (I can't be bothered to do the maths with seat pitches) six regular rows of Coach with nine of these, then you go from 36 pax to 54 in the same space?
That would allow different fare grades to be given to those seats for those who want to skimp and other folks can take the regular Y. Mum and Dad can have seats and the teenagers can perch.
Some a/c might have some Biz seats up front, some Y and some Cattle. Sounds like it could work. You would have to balance total numbers and loos and doors but that's just matching the regs and the maths.