Relationships. I'm in (and likely near the end of) my first serious one. When we met, I felt I was more attractive, and had the power. Over the past year things have gradually shifted. Now I feel like a worm. Happened to you?
Incredibly vague OP, but I'm gonna make a philosophical soliloquy based on what I think you're hinting at anyway.
In most relationships I believe you have a dominant and a submissive half, and as long as the individuals involved are both in the position that feels natural to them everything will go smoothly. It's not inherently better or worse for the man to be in charge or not, the important part is if that lines up with the individual's personality. When those roles start to slip out of alignment that's when friction occurs.
I don't think it's necessarily healthy to expect the individual in question to somehow adjust themselves; it can work but I think it's usually more likely to result in conflict and suppression of healthy self esteem. People change over time and usually a shift in this dynamic represents a drift apart, outgrowing that partnership, if you will. We are taught that couples should exist for love and love alone, but in truth a person's financial status, direction in life, their ambitions and long term trajectory are very important. We shouldn't be ashamed to admit it if we are no longer a perfect fit. Sometimes life can take us down converging paths.
(There's also neutral relationships that share power and responsibilities equally, but I think they are much less common, and most people who think they are in one probably aren't. This is very broad stroke stuff. It's also not impossible for the other partner to change or adapt so that the partnership is complimentary again later down the line. But again rare.)
A lot of people don't say how they feel and over time end up in a state of appeasement. After the honeymoon period problems start happening and the trouble is that women often like to talk more than men. I had, and other males I know have, a tendency to just let the sadness build and go with the other person which leads to feeling terrible. Read 'No More Mr.Nice Guy".
You do have people that have been together for a while that cannot say the simplest of things to each other, or have a discussion about anything but the weather.