This is a really hard one to guess. What's actually in my "collection" is kind of nebulous. I have thousands of CDs, albums, and cassettes, terrabytes of digital music, and access to nearly infinitely more with various streaming services and such. There are definitely CDs I've spent money on and still haven't even unwrapped them. Certainly too many I either haven't gotten to or haven't listened to in years, decades in some cases. But that's just the consequence of having broad interests and a penchant for exploration. As long as I have the physical space I couldn't bear the thought of getting rid of any of it. I never know when a spontaneous urge to hear something I haven't heard before or in a long time will arise. And streaming is unreliable, some albums just aren't available, and they're pulled down for various reasons all the time. So I wouldn't want to part with anything I don't have to, there's no guarantee I can access it again.