> it wouldn’t necessarily get rid of an open web as it’s entirely optional The devil is just right there. If an implementor is dominant, and that the feature s

> it wouldn’t necessarily get rid of an open web as it’s entirely optional The devil is just right there. If an implementor is dominant, and that the feature starts to be used extensively by banks / utility providers or other essential utility, nothing prevent those users to enforce using browsers implementing it, event if it's optional per spec. The feature then become de-facto mandatory for all implementors, and in the long run google can start refusing serving apps on non-compliants to their de-facto standard without much fuss outside the tech people.