My own music tastes change over time. I don't listen to the same things I listened to 25 years ago - at least, not often. I want new music from time to time, especially if I'm walking places often.
That's the thing with streaming. I'm OK with paying an amount that is less than a CD was 25 years ago just to have a bunch of music at my disposal. A bunch of new-to-me music from various genres and from various places in the world. It isn't like I'm going to purchase physical media any time soon.
Is the service forever? Nope, probably not, but that's an issue for later me.