Yes, the phrasing is used (informally). No, you cannot drop the "about" because "is" cannot carry the meaning, which is more like: Correct swimming consists of / OR/requires making the right movements and having the right rhythm.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
azzCan one say a. Correct swimming is about making the right movements and having the right rhythm.One can. 'is about' ~ 'involves' ~ 'has to do with'