> Google, and so many others, failed to do the logical check: If this was off by default, would users enable it? If not, then it doesn't need to be a feature.

You fundamentally misunderstand the forces at play if you think this is a failure on their part. They are incentivized financially to be user hostile. There is no magical moral compass embedded within the market that rewards those who make product decisions based on what people want, or what's good for them. They're an ads and tracking company. Approximately nobody would opt-in to their dragnet. Their whole operation is using free services as bait to track and manipulate as many aspects of human life as possible. There is no meeting where someone internally might say "hey, what do you think the user wants, what's best for them?" It's "we want the users to feel/do X, how do we get them there?"