It is not unrealistic to expect a surgeon to straighten a deviated nose. Twisted or crooked noses have many underlying causes, include cartilage, bone, and skin. Most deviated noses are due to a deviated septum, which contributes to breathing issues or nasal obstruction.
Depending on the exact cause of a deviated nose, most rhinoplasty is relatively successful. However, surgery is not 100% guarantee of perfect results. Patients may require touch-up or revision nasal surgery, especially those with prior history of nasal surgery or trauma.
Based on the photograph alone, it's difficult for me to appreciate a deviated nose. Only after a comprehensive evaluation of both the internal and external nose, can a rhinoplasty surgeon provide the best option for you. Generally, most plastic surgeons will give you their honest evaluation. If you feel otherwise, then find another plastic surgeon. Best of luck.