Record companies promoted the advancement of the arts by promoting new music.
I would counter with that also increased their profits. The label that took a chance on some white guy from Mississippi doing a hybrid of hillbilly and "race music," while offending people on television shows and also seeming somewhat dangerous, paid off big. Chris Blackwell made a lot of money from taking a chance on Bob Marley. Even the Beatles were scary to some companies, but taking the leap of faith generated a fortune.
Today they are only concerned with the advancement of profits. That means sticking with genres that are tried and true sellers.
The thing I remember from the record company people of the 50s and 60s was that they trusted their gut instincts. Their idea of a focus group was "I like these guys" and if the telephone switchboard lit up when a DJ played a song, that sealed the deal. Of course they wanted to make $$, but they felt an affinity with artists. They were artists too, in their own way. There was an element
of patron of the arts. Perhaps they weren't musicians, but they were creative people.
They are far less enthusiastic about developing new talent and promoting new music with uncertainties of return on investment.
I think that's it in a nutshell. That's why Hollywood went for franchises and blockbusters. They knew if they did a franchise movie, it would at least make back the investment. Something like the first Star Wars was an anomaly...it was a throwback to the old school, trust-the-gut mentality. Which of course, turned into a franchise
But any entrepreneur will tell you that safety will take you only so far. At some point, you need to take a chance on something disruptive. I wonder if there are any musicians out there going truly disruptive stuff? And if there are, how would I even know about it? Live venues are getting harder to find...sure, you can get exposure on YouTube, but the noise-to-signal ratio is huge.