[giantrobot]

Because it was broadcast to your iPod. Where iPod means a non-networked personal media player which in the 00s overwhelmingly meant an iPod.

The distribution model was a client subscribes to the RSS feed on their computer, downloads new episodes (from the publisher's website), and then syncs them when the "iPod" is synced to the computer. Many PMPs but the iPod especially defaulted to syncing your computer library when plugged in (to charge). So the iPod just received no episodes of podcasts when people plugged them in to charge at the end of the day.

When iTunes added explicit podcast support it became even easier to subscribe and sync podcasts. This was and remains a good distribution model but Spotify et al have done their damnedest to co-opt the term to mean content exclusive to their platform.