As for artists getting paid for or not depends on many things. Some years ago a musician said that he's glad that his music had been made available since his records had been sold out already in the sixties and the recording company had no intention of re-releasing them. So although he got no penny from YouTube, new generations could find his music and come to see his gigs. So in his case copyright violation brought him more audience and thus some income. It's safe to believe the musician in question didn't play in bands like the Rolling Stones or Beach Boys, nor was his name McCartney or Jackson...
I wholeheartedly agree that people should get paid for their work. In the case above the pay came the "wrong" way but was probably more than a re-release would have brought under the line. But yes, it's complicated. If I download a Beatles' or Elvis' album from the Internet, there'd be one record less sold and the income from it lost. But who would lose if I downloaded the album "Inferno" by John Buzon Trio? If something is available second hand only, then no matter how highly priced the items were, the original artist or the publishing company won't get a penny. Where to draw the line of everlasting popularity and obscurity?