Did you actually read the whole thing? Shupe most definitely did NOT try to delegitmize all transgender identities. What Shupe did, however, was to acknowledge that their own dysphoria is not the result of an immutable internal characteristic, a special "female brain" or "female soul", but rather is a manifestation of a paraphilia.
Shupe in no way denigrates or says anything uncivil about *all* transgender identities, in fact they seem fairly supportive of the category of gender dysphoria that you have.
A large portion of Shupe's view is based on the fact that the medical care he received at the very beginning was inappropriate and wrong and harmful to them, as well as to other people who are like him. They were not treated for the condition they actually have, they were treated for a condition that is en vogue at the moment. And that treatment did not help them, it made them worse.
Shupe was misdiagnosed as being transgender from the get-go. As was Keira Bell. And all of the other people who have detransitioned.
Are they all brainwashed? Are all of their identities up for debate? Is the harm done to them and to their bodies, is the lack of appropriate clinical care, something you think is just fine?
Look, Boudicca, I have compassion and sympathy for you. But I ask you to take just half a step back, and try not to take this discussion as personal. I accept that your gender identity is appropriate for you, and that you have gender dysphoria and that transitioning is the appropriate treatment for you.
I ask that you step away from your personal journey and ask yourself whether transition might, just maybe, NOT be the appropriate treatment for everyone. Is it perhaps possible that some people are being misdiagnosed?
Autogynephilia is an actual diagnosis in DSM-5, by the way. It's one of the sub-set disorders under transvestic disorder, which is classified as a paraphilia. People with transvestic disorders ought to be able to access appropriate clinical care and treatment for their conditions. Being tracked onto the incorrect diagnosis of gender dysphoria, with a direct lane to medicalization, is probably not the appropriate treatment for them.