Spotify annoys us, being used to free and open things on the hobbyist's dime, but as we smugly advise on HN when it's convenient for us: sometimes you need to shake up the business model. That's what Spotify might be able to pull off for podcasters.
Not sure it will ruin anything, though. The people who prefer to beg for donations in their podcast episodes are always free to do it. Our unwillingness to support content creators is what ruins things and puts everything behind an explicit paywall.