More widely, many, if not all, of any recommendation algorithm in any field (music and beyond) are not 'intelligent' (meaning smarter than the right human) in any way whatsoever; as noted, usually some tag sorting going on - and where items have been auto-tagged vs manual makes no difference to the quality; you're still dealing with a programmed personality when auto-tagged.
However, they do (appear to) 'work' (exhibit intelligence) when it's performed on a topic of which you know little; there they offer a helping hand.
It's a damn shame because the open nature of podcasts is one of the most appealing things about them. I get where they're coming from though.
If they weren't spending ungodly amounts of cash on podcasts (cough joe rogan) they could probably buy pandora (just guessing, not looking at any actual numbers) and replace their recommendation engine with theirs.
I spent a good 10 minutes trying to figure out what the hell had just happened until I found a page promoting Spotify's dynamic ad insertion for podcasts.
This is an inaccurate assumption is how. Podcasts are audio adverts with interesting segments haha.
Ok maybe not that bad, but it's nowhere near 'few or no ads'
I'd definitely qualify the worst case of 28 out of 30 minutes being actual content to be "few or no ads".