I'm not sure that's entirely bad. I met up with my cousin (nearly 20 years younger than me) and one of her first questions was "Show me your playlists! Music is how I get to know people." We spent ages talking about genres, recommending bands to each other, scrolling through each other's Spotify libraries and offline MP3s. I was thrilled that she was interested in a wide range of genres, across several decades. Far more diverse than when I was the same age. It's still social to be recommending music and trying to find new bands your friends will like.

As for knowing the same songs, I made friends through genre-related social groups - the goth/industrial nightclubs, and the Eurovision fanclubs / events. It's nice that generally everyone knows the same Max Martin songs, but there's deeper friendships to be had at clubs where everyone knows your obscure niche - whether it's arguing that Euphoria is still better than Heroes, even if Mans & Petra are the best hosts. Or if it's goths bitching over the shared experience of falling down the stairs trying to get onto the goth club dancefloor before Dero from Oomph yells "Gott Ist Ein Popstar" or "Augen Auf, ich komme"....

Don't worry, they still rally together around songs as they go "viral". Music has always had a big social component and always will. It's wired into us.

Damn that’s scary. A world where no one has anything in common. I’m in my 30s and my friends and I reference songs from our childhood all the time. Shows and candy and all sorts of things.

If you don't have anything in common with others then you're both mutually doing a really bad job of sharing your favorites with each other. I love getting musical recommendations from friends, and most of my very favorite music ever comes by way of friends, rather than me having "discovered" it "independently" (whatever that even means).

Interesting point. What helped you become friends with those people in the first place? For myself it's usually a common background or shared interest in something, which for example enables us to jokingly rank the best video games, which we are all familiar with from our childhood.

Honestly it's mostly about collocation, which studies have shown to be the most powerful factor in friendship formation. My best long-running friends that I'm still in regular contact with are all people that I met freshman/sophomore year of college because we lived on the same floor in the dorms. Now obviously most of the people on my floor I didn't make friends with, but I did make friends with the ones that I got along with. And yes there's some shared interests involved as part of that, but proximity was more important. I was in the CS major and I actually didn't make a lot of friends in the major at all; we didn't gel well for whatever reason and the classroom environment wasn't suitable for getting to know people. So my college friends ended up being a diversity of majors plus a lot of landscape architecture majors, because my most outgoing friend was in that major and he made a lot of friends in the major because of the nature of it (lots of time spent together in close quarters in the studio doing project work).

So I wouldn't say I've explicitly made many if any friends over shared interests in music, but then once I had friends for whatever other reasons, we shared a lot of music with each other. Hardly any of them weren't "in" to music, and indeed some of them quite the opposite; they ended up in a band together (and I would occasionally incompetently noodle along with them on vocals/bass/guitar, but I wasn't remotely good enough to play out like they were).

Remember the 90s? https://www.youtube.com/watch?v=5pa6SGYWADU

E.D. Hirsch, Jr. wrote "Cultural Literacy" in 1987, with an update in 2002 as "The New Dictionary of Cultural Literacy". It's a huge collection of thousands of words/phrases/concepts/devices/people/places/etc, across multiple categories, that most Americans will already know the majority of their meanings, or at least find them somewhat familiar. I personally like randomly looking at the proverbs and idioms and sometimes finding parallels in other languages. It'd be interesting to go through it at random with a 7th grader and see what they've picked up -- like who says "there's more than one way to skin a cat" these days, but also who grew up in the US and doesn't understand its meaning? The book contends that about 80% of the knowledge shared by the literate has not changed for over a hundred years. Meanwhile for the 20% that changes (or is brand new) Asimov once wrote a chapter (9 in http://www.arvindguptatoys.com/arvindgupta/asimov-on-numbers...) on how so much once-common knowledge has been happily forgotten -- who needs to know about compound addition?

For the professional context, https://apps.dtic.mil/dtic/tr/fulltext/u2/a219064.pdf et al. claim you need to know 70k plus or minus 20k things in your field to be an effective expert. I think it's also why it can be easily rewarding to chat about work with colleagues, you both have a lot in common just on the basis of the shared profession.

In short, I wouldn't worry about running out of shared knowledge, nor even shared preferences and tastes, for yourself or for the world.

In a way, that would just be a return to before the second industrial revolution, when popular music and consumer products were more more regionalised. "Everyone in the world, or even the country listens to the same thing and drinks the same cola" is a recent phenomenon, and arguably not that valuable a phenomenon.

In practice, though, I'm sure there's quite a bit of sharing musical tastes between friend and interest groups; it wouldn't be literally everyone listening to different things.

I would wonder does increasing consumer choice ultimately erode generational identity a bit, though. So much of the "what is a boomer/gen X/millenial" is founded in what popular culture everyone was consuming in a given decade.

Ha thats a sweeping statement mate.....No one has anything in common?