Exactly, this isn't FM.
I was in a similar situation back when I first graduated and was writing for an agency. We had a boss who has been successful in the past but wasn't doing so well now. They became increasingly draconian, irrational and hard to work with. As the months went on, everyone's workrate and quality was down, because being in that environment every day, knowing you could be the next one to be fired or demoted for something minor, it wears you down. It makes you feel like ****. The fact that there are fans (or clients) in my case, real people who have invested in you and deserve better, it doesn't matter. You try to be better for them but the bottom line is you just won't perform in those circumstances. This is something you will see in every area of life, it doesn't matter if we're talking minimum wagers in a supermarket, Wall Street bankers or footballers on millions. People are still fundamentally people.
What you need in circumstances like that is change. You're not performing to your best, but when you have a bad boss like that, the blame ultimately doesn't fall on you. This is a key thing in any management as well. You are ultimately responsible for the output of your subordinates because that's your job. People don't seem to understand this. Management isn't all about making the right decisions, seeing the big picture, being smarter and better. It's about being able to manage. When the majority of your team finds you so objectionable that their work is suffering because of it, the buck stops with you.