Well, blazekenny I think you are right! Not piano repertoire, but probably all inspired art in existence is masculine.
Why?
Obviously, because they were created by men.
There is a pretty Freudian explanation to that: Men simply have higher and more persistent libidos. If not used in sexual activities, or rather if one is not able to do so (I'm not sure if celibacy would work), it is discharged in an other way. Werther commits suicide and some people create art instead. Therefore, it not only boosts your creative potential, but is almost always the reason for the creation of great art, especially in the romantic era, since in other eras there were and are other purposes and ideal contents for art. That's called sublimation.
This may sound kinda weird, but I like that my deep love is unrequited, so my sexual drive remains repressed.
Brahms, Schubert, Beethoven, Mahler, Berlioz, Janáček, Berg, Tchaikovsky, Chopin, and probably Rachmaninoff are all great examples.