The only question was whether Ma Ling would want to keep using it, given that it was the art used by the sect that had killed her mother, crippled her father, kidnapped her, and altered her memories. The art itself wasn't at fault for any of that, but Yang Qing wouldn't be surprised if Ma Ling developed an aversion to it because of her history with the Ice Emerald Sect.
And if that aversion did take root, she might decide that switching arts was the best course of action for her, though she would be restricted to the choices available to her. She had already used the Glazed Ice Emerald Art to establish herself in the Qi Refinement Realm, and to form her first three pillars in the Foundation Establishment Realm. Because of that, any replacement would have to be another yin-based cultivation art.
