Being a gatekeeper really must seem kind of pointless in a magical wonderland where everyone can fly.
In EoSD she manages flying around, but I guess it would be best if she stood on the highest place of the scarlet devil mansion if she has to watch out for flying troublemakers. Guess it would be more of an airspace regulation type of job kinda, although without any long rage communication skills she would have to move from one place to another and/or coordinate fairies( not happening let's be honest). It would probably be really tiresome.