The problem is that some (maybe most) of those "old culture" people are also the ones keeping the current organisation going (in whatever state that might be).

The problem is that some (maybe most) of those "old culture" people are also the ones keeping the current organisation going (in whatever state that might be). I've seen this in several organisations - staff representing the old order who had been with the organisation for years (or even decades) are got rid of. And because there's a feeling it's better to rip-off the plaster quickly - you get rid of multiple people at the same time. And then things start to go wrong.