It's both. We didn't play a high pressing game when Redknapp's side was tearing teams apart. Even the first season of AVB where the football wasn't great but we were winning more than losing. As soon as the fear factor goes, opposition teams are more encouraged to have a go.
I don't disagree with anything you say about our decline by the way. I'm just saying there's another dynamic.
I don't think the high press, high intensity game is sustainable for most teams. You need young and fit players to do it. Invariably if it's a success, those young players become household names and fan favourites but they stop being able to handle the system by 26/27 and ideally need to be moved on (not all)
Fans won't tolerate it though and will accuse the club of being unambitious and a selling club. So they keep the players until they're broken and can' handle the system anymore and end up where we are.