If by "own", you only mean physical product, then that would be in the tens of thousands, but ownership, to me, includes digital as well and so that would push that number into the hundreds of thousands. Just in iTunes alone, I'm listening to a library of nearly 200,000 hours from a quarter-century of curation.
Streaming is so elaborately done around here that it would be TMI for anyone's interest.
Spotify really is like a jukebox (as well as Bandcamp and many others ... hell, the Internet is a jukebox really).
Streaming, in general, is still growing at an alarming rate and so that can be expected to continue until they run out of monetization ideas which doesn't look like it'll be anytime soon.
Pretty glorious times, methinks.