Not sure why you are being downvoted since your statements are correct.
Few advertisers rely on user agent for ad targeting since it can be easily mocked with each HTTP request. It is used for fingerprinting, sure, but from my experience, mostly as a way to identify bot traffic.
It is also true that the advertisers that fingerprint people rely on JS that executes WebGL code in order to get data from the machine.
Finally, you are right that it doesn't make sense that a company like Google dictates these standards since they have a conflict of interests worth almost a trillion dollars.
Few advertisers rely on user agent for ad targeting since it can be easily mocked with each HTTP request. It is used for fingerprinting, sure, but from my experience, mostly as a way to identify bot traffic.
It is also true that the advertisers that fingerprint people rely on JS that executes WebGL code in order to get data from the machine.
Finally, you are right that it doesn't make sense that a company like Google dictates these standards since they have a conflict of interests worth almost a trillion dollars.