My favorite underappreciated aspect of the iOS app store is its absolutely friction-free cancellation.
It makes me much more willing to trial a subscription service because I know I won't have to spend an hour of my life on the phone with a lovely Filipino man to stop that service.
Google Play also has that if you subscribe through there (which might be more expensive because of the fee Google takes), plus an easier refund system if you subscribe to something and decide it's not worth paying it
It is one reason that with this switch allowing apps to send me outside of Apple's Ecosystem to subscribe, I hope that developers realize that if they make this the only option there are likely many people like myself that just won't subscribe to your app. I am far more likely to try a subscription that costs a couple dollars a month if it is through the app store instead of through some random website.
It makes me much more willing to trial a subscription service because I know I won't have to spend an hour of my life on the phone with a lovely Filipino man to stop that service.