You don't let the audience down by creating content they don't want to read.

I have to say I also am in the same kind of boat as the male Tweeter who DM'd you, I'm less likely to read your stuff if I know that the article will 90% of the time be: either self hating, or vitriol against others, or complaining about your life. It's not because you're wrong to write what you write, it's because I personally don't get much out of it on a personal level since I feel like I've now taken away the key points by now and don't have more to learn from these particular kind of articles.

You are free to complain, be down on yourself, get angry etc as much as you want. Your feelings are valid. Do others necessarily want to read it though? Well the numbers speak for themselves.

You don't "owe" the audience anything, you're not "letting us down" by creating stuff we may not like.

At the same time, readers don't owe you clicks if your content doesn't vibe with them anymore.

I'm sure that you have a core audience that is a perfect fit for every single thing you write. I'm clearly not that core audience. I think that there will be a tricky balance to try and strike between appealing to the core audience and at the same time appealing to the wider audience of Medium to try and get the higher numbers. If you just write what you want to write, not everyone may want to read it. That's not a sign you let people down. It's just that different people get different things out of a person they follow. Some will be getting exactly what you want them to get, others will get something else and will move on when they feel they're no longer getting that.