For me it's not even a matter of paying. I have the disposable income and currently follow two Patreons that release podcasts. Luminary has several podcasts that interest me and even lowered their prices not too long ago. But the moment I'm told I have to use an exclusive app to access them I lose interest. I subscribe to too many podcasts already and can't be bothered switching between several competing apps.
Spotify's podcasts are all free, and I still seldom use the app to access their exclusives. If either of those companies release RSS feeds for use in other apps I'd be much more inclined to subscribe. Stitcher Premium has fan-made RSS feeds that work great (and seem to have tacit approval from Stitcher to remain online). If Luminary did something similar I imagine there'd be some loss of anonymized listener data, but there'd probably be an uptick in subscriptions, too.
Basically, there are ways to keep offerings exclusive while not necessarily being app-exclusive.