Does everyone who expresses gender variance think of themselves as transgender? The answer is of course no and there is plenty of proof of this all over the internet. It's also an irrelevant question because how one lives is far more important than their label for themselves.
When core identity isn't questioned the expression can be joyful and free of distress because nothing needs to be done to perturb an existing life other than find a balance point. However, once dysphoria is present it is another matter altogether.
Many older transgender people misdiagnosed themselves because they had made life decisions whereby further advancement was not possible. Hence they settled on a formula that worked (if imperfectly) to be able to keep marriages and careers intact.
Over the last few years we have invented more categories to describe how people feel which ultimately changes little about how to proceed. The action plan is not developed via a definition.
My own journey had to be extremely slow and planned out because, despite my marriage breaking up, I could not investigate where I stood on the spectrum without taking risks regarding the welfare of my children. As it turns out I fell just short of a medical transition I might have undertaken were I 25 today and starting over. Fortunately, I blend in well without alterations plus I have developed elephant skin.
What became paramount was taking something I mistook for dress up as a young child to the level of seriousness it deserved which was no easy task. As I met people over the years who did not fit my profile I realized I had much more work to do than I had first surmised after finding much more affinity with people who needed to transition. Only that my natural skepticism obliged that I do my own homework rather than pay attention to the orthodoxy of the day.