I’m on the fence regarding the latest Apple TV and new iOS and need to have a question answered that might get me to do it. To add paying sites like Peacock, HBO Max,Paramount+ with Showtime, Hulu, to up next, do I have to subscribe to them via Apple in order for them to show up in Up Next? At the moment my subscriptions are via scattered sources. There would be a lot said to have all pay apps in one spot for billing. For free sites like Pluto and Tubi, can those be added to up next?
No. The only requirement is that the app be compatible with Apple TV. Some of the services you mentioned are not even available for subscription through Apple, but are compatible with up next.