Relay was (yup) one of the third party apps that survived the API-calypse. But this sort of model is unsustainable in the long run, given that the competitor (the broken native app) is free and unlimited.
The obvious future monopoly of the broken native app is bad for the platform in the long run, given that Reddit always sucked off ideas from third party apps; and now there’s no incentive whatsoever to make it better, after Reddit Inc. killed the better competitors.
Data-mining, right? It’s that sort of shady as fuck activity that every business and their subsidiary dog is doing nowadays. If not for that, theoretically they could feed the advertisement directly into the third party apps, or demand them to show ads from Reddit in order to operate. (They’d probably do it - their devs were eager to dialogue, before the recent events.)
It’s one of the reasons I’ve moved over to lot of Foss apps over the years, and opting for using lite apps through the browser over downloading official apps.