And Spotify. And Apple Music, to an extent. And even SoundCloud.
> They helped struggling musicians survive, giving them a chance to make it,
Survivorship bias. You're completely ignoring the artists that never got the attention of distributors, or got immediately dropped, or dropped after the first disappointing (by studio standards) sales, or screwed out of revenue and royalties, or...
Or those who never got a chance at all because Sony or Warner paid radio stations to promote who they wanted to promote: https://www.npr.org/2005/11/23/5024411/warner-agrees-to-sett...
> Labels still do this today, but it's just the number of opportunities for musicians is smaller.
Labels still do this to the same extent as before. They spend about as much money and, percentage wise, keep as much money as before. It's even easier for them because a whole layer of physically printing and distributing media (tapes and CDs) is gone.
And the number of opportunities for artists increased, but became more complex.
In 2012 an otherwise unknown outside South Korea artist reached a billion views on Youtube resulting in worldwide tours. Now there are millions of unknowns on the same platforms. It's never been easier to promote your art, and it's never been more complex because there are so many others.