This is red herring. I doubt you could find a single musician who would tell you that they wouldn't be creating if they don't get a lifetime to exploit the work. Further, you can see proof of this through history. Copyright used to be much shorter and people still created.
Most people who create, especially people who make good music, do it because they love it, not because they will get to exploit it.
Someone is going to render that art for consumption in exchange for that cash. My conviction is the artist should have right of first refusal to grow rich with that cash. I confess this conviction is a moral conviction, driven by a sense of fairness, not efficiency. “The suckers compulsively produce it for free,” doesn’t find much purchase with me.
Do you think they write more or less because they make money from it?
If I shared one song and made money then would the chances of me sharing another increase?