Actually, it's all three and even more! It entertains many, various forms being somewhat less "artful" than others (IMHO), is certainly considered by many to be fun, either as entertainment or participatory, and in many cases is also certainly an art form.
However, participation in creation of music is also an emotional activity, as well as a significant amount of work. I sing bass with the local choral society, and our 10 minute participation in the Mahler 2nd Symphony is absolutely intense, requiring great strength to sing low notes at very quiet dynamics, while still projecting to the audience, and to sing very high notes at great volume while maintaining control and clarity of sound. One must demonstrate emotional content and intensity to the audience, supporting ALL the sound with controlled diaphragm and breath support. Simultaneously, one must read both German words and musical notes and controls while also following the directions of the conductor.
So, IMHO music is all you spoke of, and much, much more. Yet, for me, I'd rather lose my sense of sight than my hearing, as I can still learn and enjoy music as a blind man, while were I deaf I'd lose something I hold very dear.
50+ years of making music