On top of that, there are applications that can have this payment flow except you need permission to accept outside payments. Shopify only gives this to established companies.
Late last year, they also got rid of unlisted applications and now all applications have to be approved even if you don't want it in their app store.
Shopify is building its moat and getting more and more restrictive. I'm very glad we abstracted all of the operations out of Shopify directly and now can use any platform or even Stripe directly. If you want to build an e-commerce store with Shopify still, use the $9/month plan and use Shopify just as a CMS and integrate with payments separately.