Then a couple of years later half the new music I found is no longer on Spotify. I've largely given up on it.
And you can't rely on automatic classifications either. But then music providers don't give you proper info for the music they provide. It's a circular problem.
And then it's a social problem, too. You may want to listen to music that other people that listen to your music do... But then you might not want to do that.
It's a mess.
If Spotify could increase and sustain the catalogue then I'm pretty sure this would work. But it feels like the catalogue is smaller, churns more, and isn't as enriched in meta-data or listener behaviour to make it work yet. A network problem more than a technical one.
Blogs, discogs and national radio actually work a lot better for me for discovery, simply because, as you say, Spotify may not even have the input data in order to then help me discover better music. Thing is, I'm not sure there is a desire (perhaps economically driven) to improve that catalogue as they would need to.
Part of what drove me away from Pandora at a certain point (maybe they've changed since then, don't know) was that they would only play a small subsection of any particular artist's work-- that is no bueno for me, if I really love them I want to hear it all at least once.
I'm in my 40s, and I still listen to an incredible amount of new music. That is across everything from mainstream rock and pop, through to jazz, jungle, soul, techno, house, hip hop, classical... everything (though I tend to draw the line at screamcore).
And in there last year a tiny unsigned band with 2 tracks and fewer than 900 listens (at the time) got suggested. That band is now one of my favourite bands, a Scottish punk band... Dead Pony https://open.spotify.com/artist/3lGO6uBIzoFyU6OoGMER1B?si=OT... . Since hearing them I've told my old contacts in the music business about them (typically DJs at 6 Music, a few people that own labels, and a few musicians too). Earlier this year they've been signed (nothing to do with me, though I hope whispers meandered and it helped), been featured on BBC 6 Music, and are now working on an album and one of their tracks has hit over 1M listens. I've seen them live and holy crap, they rock... destined for far larger venues than the 50 person under-arches theatre in London that I saw them...
Spotify is doing something very right when I'm not solely rediscovering things I've been listening to for 30 years, but am finding the things I'm going to listen to for the next 30 years.
I've tried Tidal, Deezer, Apple, and my own heavily loaded Plex with all of the music labelled and richly tagged... but the discovery capability of Spotify along with the playlists are their killer feature.