Respectfully you're looking at the wrong wing of the (old?) industry. Radio plays have never been a substantial revenue source, they have a lot more in common with streaming in that way, and in fact, many labels would use paid radio placement basically as a form of advertising. The tradeoff being, for the consumer, that the radio didn't play whatever they wanted; it played what was scheduled, with an occasional request from a lucky listener.
What streaming has cannibalized is album sales, which is the problematic aspect. The fixed price-per-month to access a vast library of music is a killer value prospect for the consumer, which is why Spotify et al have succeeded as they have. However, again, it's bad for the artists; they don't make shit. And I mean, think about the economics there and it'll become evident why: previously to access between 10 and 20 songs depending on the album costed you about $10-15, one time purchase, but it was yours for the life of the media. Now you're paying (if you're paying) about $15-20 per month to access all of the music ever. And yeah there's less cost, no printed CDs, no shipping, no retail markup, but come on, if you have 4 CDs in your spotify library and are on the most expensive family plan, which IIRC is about $30/month, you're already ahead by 50%. That doesn't bode well for the artist's revenue split.