[rektide]

> I'm not convinced that Google intends to maximize the automation and decentralization value of that kind of verification.

This seems like the core question/hypothesis you have as to why you might suspect this particular technology. If you have other specific concerns or fears or misuse, please let me know, but I have not identified anything else I can speak directly to. I dont understand Google nor their incentives, but I do understand the IETF drafts for this technology fairly well.

As to this specific question, the validation for Signed HTTP Exchanges (SXG) is the same validation that happens with any web page you would load via https://. This is not a perfect system, but one we have lived with, & SXG introduces no new complexities to it.