Does a composer have to study counterpoint?
Not necessarily. It’s possible to write beautiful homophonic music, even if one never studied counterpoint. However, the best composers of homophonic music did study counterpoint – vocal (Renaissance) and instrumental (Baroque) counterpoint. Mozart studied counterpoint. He also admired the polyphonic music written by J. S. Bach. The students I taught who studied vocal counterpoint (Fux, Gradus ad Parnassum) were better at voice leading then the students who didn’t. If you’re capable of studying hard and patiently, I advise you to take lessons in counterpoint. Otherwise, don’t even bother.