I think you're right, but I also think the cause-and-effect is pretty bilateral. Designing implementing and maintaining that kind of decentralized HATEOS/"semantic web" (there's a simlarity, right?) infrastructure, in a way that actually works well... is very expensive. More expensive than it's (non-"political"[1]) benefits. People do things where the immediate benefit is worth the immediate cost.

That is, there is something intrinsic about the architecture that is both suitable to decentralization, and more complicated/expensive for not enough obvious benefit to those who pay the expense. And these are related.

[1] "political" in the sense of "where the power lies". And they are real benefits there to decentralized infrastructure (at least for those who aren't going to be in the center). But the way our economy and society works, they don't produce funding to create.