I've heard there is a test either in the works are available that can tell you if you actually have gender dysmorphia/dysphoria. I wonder if you gave that test to someone who was either diagnosed or just thought they were trans, would they accept the results? And even if they did, how many would still pursue transitioning?

Well, insiders have found this is the test to apply what people have gender dysphoria's description of someone who has it:

You have a great need for other people to like and admire you. You have a great deal of unused capacity, which you have not turned to your advantage. Disciplined and self-controlled outside, you tend to be worrisome and insecure inside. You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations. You pride yourself as an independent thinker and do not accept others statements without satisfactory proof. You have a tendency to be critical of yourself. At times you have serious doubts as to whether you have made the right decision or done the right thing. At times you are extroverted, sociable, while at other times you are introverted, wary, reserved. While you have some personality weaknesses, you are generally able to compensate for them.