Has there been any App Store apps that go with this approach?
As long as Reddit provides some API accessible to a non-logged in user on the web, there’s going to be a way to scrape it. If you push that scraping into the start of the app then it’s be distributed without any clear way of blocking it.
You could even have the app fetch “how to” updates from a a central site rather than pushing app updates so you don’t have to wait for App Store approvals to get around scraping updates.
We could call the end user’s program for accessing the site a “user agent” as it acts on behalf of the user to fetch and display the content that the user wants to see, in the manner the user wants to see it.
It could be an open-ish format, then you could potentially support alternate sites like HN as well.
That would be such a nightmare between constantly changing UIs, A/B testing, and the fact that new reddit is a broken mess even when running in a normal browser where it's made to run.
For a hobby project you could maybe get away with scraping a GQL bearer token and issuing requests as if you were an official Reddit client. Or you could even request the HTML and scrape that. At the scale of these third party apps that approach just wouldn't work.