Sure, but if you game this out, it still comes down to whether or not your opinion is that this data should be public. That Steam's methodology happens to be op

Sure, but if you game this out, it still comes down to whether or not your opinion is that this data should be public. That Steam's methodology happens to be opt-out sharing - in other words their opinion is it should be shared, because people don't change defaults - doesn't change that there haven't been any known major harms and many major benefits, especially in the opinions of game developers.