Not in all MA. Some practice being light on the feet and still being rooted. "Float" and "poor rooting" aren't antonyms in all styles.more light-footed
From a wrestler point of view, it's NO NO to be "light footed". My wrestling teacher doesn't event suggest me to train running. The words "float" and "poor rooting" are both bad terms in MA. It's always better to have your gravity center to be as lower to the ground as possible.