Major problem I see is the additional moving parts. Will always lead to breaking and more maintenance, which I don't see the airlines wanting to deal with
Problem 1: Moving parts
Problem 2: FA's literally have to be involved with every person sitting down.
Problem 3: Elites board first AND want the front of the plane, so the aisle width benefits are negated immediately.
Problem 4: Some people sitting in the lower middle seat are going to feel like they are in a pit
Problem 5: It's different, and no one likes different