I personally don’t see anything wrong with it. Wearing a burka yea, I doubt one can even dance in a burka. She looks very professional.
Her look might fly in a local student performance, but professional ballet companies have dozens of qualified applicants for each opening. They have no reason to accept a performer who won’t wear what the other corps-de-ballet members wear.
One of my friends has a daughter who has done ballet for years. The daughter is 5’9” tall and strongly built. No matter how well she dances, her chance of a professional opportunity is slight. They don’t have to take a dancer who’s a head taller than the rest of the chorus and too tall and heavy for most partners.