I just noticed there’s a new rule of existing apps must have at least 10 paid installs, before allowing to submit new app, in the launch guidelines : Submit your app for review
I understand Shopify’s motivation to stop mass submission of apps, and agree this is a good direction.
I would like to suggest to allow exemption for Unlisted public apps, there’s scenarios where devs create unlisted public apps to serve their existing clients, perhaps clients with multiple stores but not on Plus yet (creating custom apps for each store would be too time consuming and complex to maintain), these apps are never public, but they still undergo the same App Store review process, and might probably not reach 10 paid installs in their lifetime.
I hope Shopify can amend this guideline, to allow apps to be submitted, just not visible on App Store, until all existing visible apps reached 10 paid installs.