I’m sure there are still tens of millions of these iPods in use, and will be for years to come. They’re great for working out. The hardware form factor isn’t what did these in — it’s the antiquated notion of having to sync audio files to them via a cable connected to a Mac or PC. If the content on your audio player isn’t coming to it over the air, mostly likely streaming, it isn’t relevant.
If you don’t use streaming though, the iPod is a far better music player than the one on iOS. The only negative I have about my iPod Classic is the physical vibration of the HDD spinning up between songs. If the hard drive dies, I plan on replacing it with an SSD.
When iTunes can successfully sync 25,000 AAC / Lossless audio files to my iPhone via WiFi or Cellular w/o crashing, I’ll ditch the cable. My iPod, iPad and iPhone plug into my iMac as soon as I get home, sync upon connection and are ready to go the next day fully charged and synced. It’s a habit I won’t be giving up easily because wireless syncing is simply too slow and streaming eats up too much data, not to mention I can’t really stream where I live. The cellular connection is really crappy. 3G is considered good, 1X is average. I think people in cities haven’t seen a 1X icon in years on their phone.