I agree and understand what you are saying

> equates to an illness

It really seems like we have overlapping and limited words here. I think there isn't a clear distinction between "illness" and "disorder" and this confuses people or isn't helpful in curbing insensitivities.

I think we do have to acknowledge that if we want a safer environment for trans people, a safer environment in the sense that it relies on the mutual cooperation of currently dismissive and insensitive people that aren't willing to cater to people with "mental health issues but not that kind".

Where is the line between "mental health issue" and "mental health illness" if both decrease the patient's quality of life?

An illness is an unhealthy condition, suggestive of treatment if treatment is available. A medical issue is an identifiable subject in the realm of medicine. Most things identifiable are not immediately unhealthy.

Nobody is suggesting that.