If you move to a lower grade you will soon notice all the things that can be improved/should operate differently. Maybe not at first, but you will when you know the role. And you will then probably be powerless to change anything, because it won’t be your job to approve and implement systems and strategies anymore. It’s literally “not your place.”
You’ll just have to go along with whatever you’re told to do by more senior staff, even if you strongly disagree with it for good reasons. And that can be VERY frustrating.
Don’t underestimate how stressful frustration can be at work. When you see every day how things should be done differently but you don’t have the power to be listened to. Instead you’ll just be seen as moaning or negative.
if you can unlearn things or you can let things go it may work.
But you can also learn to let things go in a more senior role, and be paid much better for it!
also, it sounds like your situation now is just a “difficult people” issue. But you get that everywhere, in every workplace. Even if you think you work with the dream team all it takes is a change like organisational restructuring, new policies being forced upon you all, someone retiring or/going on maternity etc and immediately the change can have an impact on now the team works and on staff morale.
if you’ve tried to improve things and don’t feel things have changed then maybe it’s flogging a dead horse and you just need to make a sideways move somewhere else, another team or organisation rather than looking for a grade lower. Eventually though, there will be another change that will impact team dynamics that will be outside your control. At that point you can decide to move on again. Or wait for th problem people to move on themselves and see how it goes.