It's because the definition includes things that aren't really about the object itself and more about where it is. And also how inconsistent it is, as Mercury isn't in hydrostatic equilibrium and yet is explicitly included as a planet by the IAU. Nevermind the fact that the new definition was speed voted and approved by less than 400 astronomers in a convention where 2500+ people attended, let alone not even being discussed with the larger scientific community.
But hey, if you'd rather dismiss my points because of an url, you do you. Not like this changes our everyday live anyway.
People say a lot more than what their words mean all the time. Having that in art is just part of being made by people.