Hypothetical: I mostly listen to Spotify during workouts so I only have about 200 streams a month. My coworker has a top 40 playlist running all day so they have over 2000 streams a month.
If we each pay $11 their artists will get $20 while mine will only get $2.
I.e. even though I never listened to a top 40 song, the artists I listened to will only get $2 from my subscription, the rest will go to the artists my coworker follows
I see what you're saying in this scenario, but in general more listens resulting in more money doesn't strike me as unfair.
I'm also not opposed to doing it the way others are proposing (dividing individual subscribers' money among their played artists instead of aggregating it and doing it by number of plays). I guess that would be one way of solving this issue, even if it's not the underlying problem. In your scenario the underlying problem seems to be that someone plays generic garbage as background noise all day and thereby generates plays that a niche artist whose listeners really love their music wouldn't generate. That's a separate problem, though perhaps changing the revenue distribution model would indeed be the best way to solve this issue.