This is a treatment that can help people. just because it didn't help you does not mean it's ineffective in totality which is the stance you seem to take.
The question posed is "Could psilocybin be the key to treating anorexia?". Psychedelics are effective in treating some psychiatric disorders - I've been clear about that - but they are (at best) only marginally more effective than most existing treatments. That's a good thing, it will help some patients, but it's a million miles from being the key treatment.