Everyone got the seat on their boarding pass so no one is obligated to move. I have seen a person sitting in the middle seat decline to move. You can't expect that people will just move to accommodate you, even if you think you are giving them a better seat.

Booking seats hoping the middle won't be occupied isn't working as much these days. The flights are fuller than ever. Himself and I usually book across the aisle from each other. That way we can share stuff and still talk, but neither is stuck in a middle seat.