The more I think about it, the angrier I get - Part 1

My job is at a breakfast diner. When I first applied, it was for a management trainee position. Honestly, I had no management experience, and I mentioned this during the interview. They said they would teach me how to do it. Indeed, they entrusted me with the management aspects they cared about. However, I feel like all I learned from them was 'If today's sales are bad, you should prioritize sending a part-timer home first' and 'This person isn't a good worker, so give them easier tasks.' I have a habit of listing out the day's tasks before starting work. Later, everyone else started helping me with my to-do list, and from then on, there were no redundant employees. However, the owner didn't think I was doing 'management.' Around the end of July, when I had been working for almost a year, he called me in for a talk about my work status. I knew in my heart he was going to ask if I was okay with a pay cut (because sales had been bad for a long time). I told him directly, 'Listing tasks is my management method, and it's true that all the part-timers have work to do, and no one is redundant. If you still can't accept my management style, then cut my salary.' The owner was silent for a moment and said, 'I've also had my salary cut before, so we'll think about whether to cut your salary. But I think there are some areas you need to change.' 'Okay, please give me an example.' I said this because the owner is truly a hypocrite, and I was eager for him to set a standard that would also expose his own double standards. '...I can't think of anything specific right now. Let's discuss it again after I've had time to think.'