Half joking: in the world where Google added JPEG XL using the normal process, the reaction would vary from mild disinterest to outright disapproval. "Google is forcing yet another image format down our throats!"

But by adding and then removing the feature, they've made it a competition. Now JPEG XL is building grass-roots support, and if/when Google relents and adds JPEG XL back, the feature will have much higher support than the boring way.