Disclosure: I work at Google but not on this.
It's just an open question, and as such, it does seem it's an afterthought, when it should be front and center if anyone care for an open web.
> Attesters will be required to offer their service under the same conditions to any browser who wishes to use it and meets certain baseline requirements.
What prevents this set of baseline requirements from being e.g. “the device is backed by a TPM from these four vendors”?
> Although a holdback would prevent the attestation signal from being used for per-request enforcement decisions, there remains immense value for measurement in aggregate populations. However, a holdback also has significant drawbacks.
“So, like, here’s a vague idea on how we might prevent this. However this idea has significant problems.” Not a very convincing argument?
> If the community thinks it's important for the attestation to include the platform identity of the application
“If we assume that we can’t actually solve this…”
Basically there’s not much in the way of answers there. Generally when you put out proposals with a history of significant pushback I’d expect the likely feedback to be addressed in more depth than this.
(I guess since we’re doing disclaimers I also work at Google but not on this.)
"This internal contradiction is further demonstrated by the fact that the proposed solution to prevent misuse by websites - holdbacks - is to simply sabotage the functionality of the system itself, by making attestation probabilistic. This is not a workable solution to the problem: if the holdback rate of requests is low enough, the denial of service to legitimate users will simply be a cost of business that websites will accept; if instead it is high enough, websites will not use this system as it does not provide meaningful enough information, even for analytics purposes, due to the high uncertainty. There is no goldilocks zone where this system is useful but not open to abuse by implementer websites. You're either implementing a feature that can - and most likely will - be used by websites to exclude unattested clients, or you're implementing a useless feature."
https://github.com/RupertBenWiser/Web-Environment-Integrity/...