90s is before 20 years ago so i won’t discuss trance as a new genre or drum n bass as something major.

Which leaves us with... trap ? Seriously ?

There are a lot of things you can do to create really new musics. Historically this was done by breeding with music from different cultures. India has quartertones and melody based rythmics, africa has polyrhythmie, etc. The problem is that nobody in the dying record company industry had the guts to finance the emergence of things created by innovators ( who obviously still exist somewhere), and since online music services recommend songs based on what you’re already liking, there’s just no chance you’ll hear those creations.

There should be a new section in apple music called « new things you’ve never heard that will probably take you a bit of time to enjoy, but then you’ll thank us for it »

Online music services recommendations is one vector. Another is just peer to peer recomandation. Eventually someone will listen to that african polyrhythmie, and if it's so good, it will pass it on to his friend.

The fact that this is not happening suggests that maybe it's just not so catchy. And something being innovative and original doesn't mean that it should also be popular. Not many want to live in a crazily organic shaped house by the famed architect, not even those who could afford it, most prefer the regular boring rectangular ones.

BTW, a long time I saw in a National Geographic a crazy african song, which seems to me to be an african polyrhythmie (not an expert). I think it's an amazing piece of music. But I also see why this has little chance of becoming popular in US, at least in this shape. Maybe some producer could "un-ethnify" it and make it more palatable:

https://www.youtube.com/watch?v=1R6WnTCpjfM

You dismiss trap, but I've heard some amazing arabic trap. For some reason, arabic vocals work very well on top of a trap track:

https://www.youtube.com/watch?v=c0xk1UQYcXs

https://www.ft.com/content/98c64ce8-8ff1-11e8-9609-3d3b945e7...

It sounds like you're drawing arbitrary lines about what is and isn't a genre. House and metal have evolved various subgenres, to the point where some the subgenres have their own festivals.

Deadmau5 uses polymeters pretty extensively and rap/trap uses polyrhythms all the time.

Yes there is a ton of electronic music and yes a lot of it sounds similar but there are new things coming out if you can dig through all the volume.

A lot of the innovation is also in sound design and not necessarily composition.