Hi,
I don't think that many of these shaped music.
I think that it made music a bit more static and controlled and less "free" from the confines of the usual rigidity that it has a tendency to suffer as a copy, rather than an original.
All in all, the blatant use of beats, is not a musical development, and is overdone, and just a passing phase in music, and history will surely show us that.
When looked at with a wider context, and include music history for the last 100 years, these pieces of software could facilitate a lot of music composition, and instead it is used for the most boring, repetitive and music that lacks desire, love, and a total dedication to the history and its inventive and creative endeavors.
I can handle, and like a repetitive beat, at times, but show me the beats in a DAW for The Rite of Spring, or a 5th Symphony! Rock music can do way better and improve on many of those and instead it sticks to the variations upon a theme with a different sounding bass note! And an even more boring drumming soundtrack!
I would like to see a lot more "anarchy" in these programs, and their use. Sadly, that is the one thing that is not found a whole lot, and as such, I tend to think that the creativity around it, suffers.
But, as a media, or instrument, it is probably very NEW and likely to improve as time goes by. And the next great composer won't use instruments but a DAW of some kind ... that ought to get a few feathers ruffled in the world of music!