I think pop music is aimed at the young, always has been post war, to be different and "new", but to be especially different to what your parents listen(ed) to. That was very effective when the medium for delivery was TV and radio. A new genre could take hold quiet quickly, but in a rolling snowball type way. Young people would be attracted to certain sub genres, but there would be variation, even if your parents said it all sounded the same and rubbish. At the same time it was guided by the record companies.
Now something or someone can take almost instantaneously with lots of people because of social media, and now it is the technology, which social media you use, or don't, which is keeping things aimed at younger people. Social media tries to feed you more of what you like, and if what you like is 60's R&R, that will be mostly what you see on social media, and if not on social media, will be the type of radio station you will gravitate to.
The option to see/hear a 'mix' of genres on something like Top of the Pops is no longer there on TV, which is mind blowing considering how many music TV shows there used to be, TotP, The Tube, The Old Grey Whistle test etc, and you may also have had a regional TV music show too.
Older musical groups, or should I say the publishers of a lot of older musical groups catalogue are not helping their artist's longevity, as they understandably try to make money wherever their artist's music is used, but charge exhorbatent fees, which has the larger effect of their artist's music not being on social media. I've seen Rick Beato talk about this.
I was one of those people who went into the local record shop every week until the early/mid 90's when the music shops started to disappear, as did the music shows on TV. New songs/bands to me are normally heared if used in adverts, when I used to watch TV, but mostly now if someone I follow on YT, or someone on a YT channel mentions an artist positively, or plays their music. I will give them a listen. My exposure as gone from almost everything, to quite limited.
I am lucky in that I can listen to a bits of a song and flip through quite quickly to see whether I like something or not. I know what I like, and can quickly decide I don't like the song, or after listeningto a few songs, the artist. There are bands I should like from my eras, which do nothing for me, but friends love.
Sorry for the long ramble if you got this far, but only just seen this thread and it struck a chord.
Anyway, one artist that has really hit with me over the last few years, and made me feel young again being so into a lot of her songs, is called Madison Cunningham. I first heard of her when a music YTuber I follow was trying to work out how to play one of her songs, and I liked the riff and the song, so went and looked for more of her work, and liked almost everything I found, which does not happen often anymore like it used to sadly. But that was just a chance exposure to her music, which is how I think most older people find new (to them at least) music nowadays.
The song was Pin it Down BTW. Great vid for the song on YT, where I think she is playing live in the studio with her band. Great guitarist too. I hope I continue to like her new music in the coming years.
Would go into the local Asda and buy cassette singles 
And I did catch my dad a couple times singing [the wrong words] to some Nirvana songs when I still lived at home lol
