They directly say what they mean in the article

> The company’s inability to maintain app performance without advertising for even a single day demonstrates the fragility of its market position.

App store ranking is based on installs. Ads drive people to install the app. Less ads -> less installs -> lower ranking. Seems like a logical consequence.

I don't know about quid pro quo but those ads are content on the internet so I would assume that would drop SEO and new installs.

One of the strange patterns with Google is that quid pro quo is hard to even filter out as in some cases it is actually a natural part of the system. Probably a bad thing.

Could the two have a common cause? What if Temu stopped buying ads and consumers stopped installing the Temu app for one and the same reason, namely that trade barriers are being erected that will make Temu unpalatable for many users, something widely publicized and known both to Temu and consumers?

its also seo linkjuice as they are links

HN can't stop being HN. Scary article about a global trade war gets interpreted as "Wait, is Google actually behind this?!"

How does this make sense? Google isn't affiliated with the App Store (note the capitals), and instead it's operated by its competitor.