I think a good counter-example is Uber, with a separate app for ordering rides (Uber) and for ordering food (Uber Eats). Both apps are still bolstering each other by the brand recognition.
Additionally, the apps could still cross-reference each other in a subtle way. E.g. maybe when you type a podcast name in the regular Spotify it could redirect you to the Spotify Podcast app. Just like the Uber app sometimes nudges you to also order food.
EDIT: as one of the comments points out, you can actually order food from the Uber app, my bad, that's not how I remembered it!