The rise in classical music is what I think is that schools are accessible to all youth and adults to learn classical music no matter where they are, music education is currently goaled to help all those play music and is really great today IMO. I still love classical but was turned off by it seeing the elitism sadly still exist in classic music today. Classical music has historically been nobleman music or church music. Rarely were peasants, serfs allowed to partake in it unless they somehow were able to afford to play an instrument. Nobleman would play instruments for fun and enjoy classical music, hence the French origins of ameatur meaning "to love". This is all over the place for time periods, I am mostly reference to at least the very late medieval times and rise of renaissance and all the way through those times till I guess oh 1800s? so 1600s roughly to 1800s at least classical music has always historically had this meaning,(Feel free to correct me at all anyone who knows better, love to hear it!) I'm more of a folk music or cultural roots type of listener these days since you learn a lot more about people and culture deeply. Classical music being on the rise in my honest opinion is more people getting access to instruments which is a very good thing, it's also the reason why there's rise in Indie bands and preferences for those genres instead because it's very "garage" sounding.
Anyway my mini-history point is, music has always been shifting but also what we see from books isn't always the case. Yeah classical music was the "stuff" back in those eras, but there was tons of folk music, think Irish session, Early American folk, Sicilian folk using classical instruments but a very different form of playing (which was looked down upon and viewed as vile by classical players way back then ironically!) So I think you'll never truly know and you have to dig super deep. I mean look at Delta Blues, it's the true origins of Rock and Roll, but a lot of people disliked it and thought it wasn't the music for them at that time. Now look at rock today...
So where is the next phase of music? I don't like Pop being generalized because pop can rapidly change or literally be any songs on the top. I also think with the internet giving expansive help to others to learn instruments, it's changing things. I mean I'm only 22 I literally remember finding nothing good on learning bass on youtube when I was like... 12 I wanna say? Now I see stuff all over! (Which is awesome!) I personally think music is heading towards garage indie, shoegaze, but also Thee Oh Sees type of Indie with a surfer twist or punkish twist. I also do not think everyone will sound alike. Tame Impala has helped inspire a vintage rise somewhat, I mean he's on the radio for a start. Do I have hardcore data to back this up? No, just my 2 cents and just my age and what I notice around my generation, but just like how we viewed Classical music being a dominated music of the past in Europe when in reality behind the doors, behind other people really folk music or the folk music of that country really dominated but was never really documented that much or given respect at that time, much of it was oral tradition, similar to what we see on the internet and even with the Blues. Anyway thanks for reading my long jumble! Have a good day all!