All these things are true. But they are far from true for the vast majority of obese people. Once you realize that you are, at least partially, contributing to the problem, you make it possible to, at least partially, SOLVE the problem.

I have PCOS, I have hereditary thyroid issues. Those all contribute to obesity. I also retain a fuckton of water when it's that time of the month. I also used to have BED.

And then I went to a therapist who basically said "so, what if you had to the power to fix a quarter of the problem? Would you do it?" I said yes, and she said "Then why aren't you?" That was a super shitty thing to say to a 19 year old, but she was entirely correct. I could fix a quarter of my problem!

So I stopped infantilizing myself, and said I was able to lose a quarter of my overweight kilos. And you know, once that first quarter was off, it turns out that taking ownership of a problem will actually let you work on that problem.

PCOS and hypothyroidism and water retention don't magically put fat inside your body. You can absolutely lose weight with them. It's not as fast as someone who is otherwise healthy, sure, and that's kinda unfair, but its also not impossible. It's just slower, and my caloric needs are lower than other people while my stomach started out at the same size and with the same demands for satiation. And yeah, that sucks. I will gain weight if I eat the same portions as my husband, even though I do bodybuilding, sword fighting and am very active. That's just how it works, and no amount of crying will fix that. None of my other problems went away, but I decided to deal with them instead of ignoring them. (Although the PCOS is much better without the obesity, and the BED was a lot easier to handle in therapy without the guilt)

You can recognise the unfairness and work on it, or you can just raise your hands, pretend it's entirely out of your control and deal with obesity. Lots and lots of people opt for number two these days.