SoundJam was great for me in 2001 playing mp3s and as most of the tone of this thread seems to confirm, everything else since then has simply given users extra grief to cope with when wishing to play a simple music file in a simple manner.
I've stuck at OSX 10.6.8 and iTunes 10.6.1 (which is still 239MB of bloat) rather than upgrade. That's where I'm staying as Apple only ever seem to make stuff worse these days.
You know nothing about the constraints they work under.
There were little iGimmicks around so it would play music, sync with the iPod, that's it.
From there it went downhill.
Really, the biggest thing I miss from iTunes, as a Google Play user, are the Smart Playlists. I loved being able to pull in every song I had from a set of artists and then shuffle through that. The "radio" features from Google just doesn't do it for me. I rarely want to listen to a bunch of music that's not in my library but which is similar to something I do have there. I'd much rather self-curate what I'm listening to. But I don't think the demand is there for that as much, now. I still wish they'd at least remove the 1000 song cap on playlists, so I could manually do this.
I would love to blacklist whoever is responsible for iTunes from ever finding work again, because it's obvious they give an ounce of care about UI design or keeping their customers happy. They really don't deserve to be working in software. If they had any honor they would be thoroughly embarrassed for producing such a horrible piece of software.