You can certainly take notes on all that anecdata and use them to design some proper experiments! But until someone gets the resources and willpower together to do all of that, the anecdata is all the evidence we have.
When a male takes estrogen it doesn't undo a lifetime of male sex development and existing as a male, nor does it give him a female reproductive system. So how could taking estrogen grant him an understanding of what it feels like to be the opposite sex?