if you build a standard and no one follows it. then it’s wasted time and money. Meta, Google and Microsoft

Google, Microsoft, and Apple also already account for the vast majority of desktop OS installations

the issue is, VPNs hide your ISPs assigned IP. till now there has been a higher difficulty in differentiating traffic from the same IP with similar metadata. the more user specific metadata that’s added, the easier it is to differentiate devices and users.

And you think that the data they get being "is an adult" or "is a child we're not allowed to collect data on", per the API part of the specification is useful for that?

If Microsoft and Google are also angling for this why is it only meta lobbying?

I think meta has some scheme to profit from this stuff, possibly also at the expense of Google, Microsoft, Apple in addition to consumers.