From what I can tell, Patreon allows you to export customer contact info, but you can't take the financial relationship with you. They're not subscribing to you, they're subscribing to Patreon. If you want to leave for another service you have to awkwardly email everyone and ask them unsub and then resub somewhere else, which will probably not work.

Streambus seems more similar to substack/supercast -- you as the content creator own the stripe account, and streambus only makes money so long as you feel the service is providing a good value to you, otherwise you can leave any time.