Seems to me that it’s almost entirely about advertising. The third-party apps bypass the advertising you get with the web page or standard app.
I was thinking earlier about how Cory Doctorow’s thesis about enshittification gets the emphasis wrong. Why is it that platforms are ever not shitty? It’s because early on, they’re funded by VC or other investor money, and can afford to prop up an unsustainable business model.
Then the free money dries up, the platform has to either charge a subscription or crank up the advertising. Both cause enshittification (particularly the latter).
Why do we ever perceive some platforms as sustainably non-shitty? It’s solely because they charged users from the beginning. They never acquired that vocal set of users dependent on the subsidized version of the platform, and so there was never an actual decline, just maintenance of the status quo. They’re still kinda shitty, but things never got worse on the platform, and they’re inevitably smaller and more vulnerable than ones that offer a free service.
Aside from that, Doctorow is on target about what happens when an investor-subsidized platform turns into a subscription or advertising-funded one. Though it’s so obvious why that it’s barely worth articulating.
Doctorow also gets the emphasis wrong when he says enshittification is just “seemingly” inevitable. It is absolutely inevitable, for the reasons above. It’s just inescapable that your platform will suffer when it goes from lots of free money to no free money. Whether the platform itself dies is a different question; certainly, they can go for a long time in zombie mode. But there’s no way around getting worse.