no_id sort of lays out the next challenge, though. Perhaps the more crucial side of things is to open up practical and interesting "masculine" ideas and not force femininity on girls and women, but the greater difficulty is opening up practical and interesting "feminine" ideas and not force masculinity on boys and men. Without tearing down the roles for both females and males alike, people will continue to treat them differently, and it will unnecessarily complicate how they see TGs (since the male role will filter interpretation of the person at some point).
And while the wordplay is clever, the lines on the t-shirts are not answers. Successful people are not just "not princesses" or "role models." The former is simply an exclusion and really only draws attention to the idea of girls as princesses. And being a "role model" is a consequence of doing something noteworthy: positive examples may include becoming doctors, teachers, business executives, engineers, soldiers, activists, athletes, and entertainers. Granted, you don't want to get into forcing any kids into any specific career either, but there has to be a more neutral way to handle them until they are ready to take responsibility for their own expressions.
It just seems off. If one wants girls to enjoy the possibilities open to boys, it's not really enough to just show "girl power" and invert the traditional role. One has to show men and women seamlessly taking on responsibilities with regard to their own abilities and desires without fussing about gender. At some point one may have to acknowledge there will be prejudice, but the best way to break down roles is to actually break them down (rather than just edit or manipulate them).