It's been frustrating watching the Spotify (and general movement) with podcasts fragmenting and going exclusive. Spotify won with music because it improved upon the existing state of listening to music and offered a free or cheap solution that was even a compelling alternative to piracy.
Podcasts for the most part were in the ideal state for consumers, almost always free and mostly client independent distributed w/ RSS. I don't think there is much of any argument that Spotify can improve that state for consumers by taking a podcast exclusive. These deals are just payouts for the hosts not investments that make the shows better. Most even very successful podcasts likely have low opex (some exceptions like NYT Daily) and don't benefit from a big pile of cash.
On a different note regarding the Rogan Deal, Spotify took ages to add video streaming support on Apple TV (main way I would catch Rogan) which basically caused me to quit casual watching. They also only recently added offline playback for Apple Watch and even then it's premium exclusive and requires manual downloading of eps. I don't understand at all why an enormous company like Spotify is so neglectful of the entire apple ecosystem.