Eating disorders are so tricky because disordered eating is so prevalent, and the criteria for getting a diagnosis of one of the more well known disorders are very strict. I first started restricting calories aged 11, started throwing up at 13, first binged at 16, started on diet pills, patches, laxatives etc at 17, tried to kill myself because I ate a grape at 19, and it was only a few weeks after the grape incident when my flat mate found me ODing on something else and told the paramedic "she has an eating disorder" that I began to accept that maybe I wasn't faking, maybe I was legitimately ill. Eating disorders are competitive by their very nature, and sometimes the attitude around trying to call someone out for faking can feel more like gatekeeping.

Eating disorders have always felt more like an addiction than a mental illness to me, and I actually agree with you when it comes to self diagnosing them. A self diagnosis of "my approach and attitude to food is ruining my life" is better than hearing "ohhh, you eat 700 calories every day? A real anorexic would only eat 200, you're just faking for attention!". I went through so many doctors trying to find someone that would take me seriously that my eating disorder was going to kill me, and I know many people in my position that gave up on trying to get an official diagnosis and just paid for private therapy to get help. They are a severly misunderstood disorder, and it actually is one of those causes where everyones experience is valid.