Because those were "free time" projects. It wasn't directed to do by the company, somebody at the company with their flex time - just thought it was a good idea and did it. Googlers don't get this benefit any more for some reason.

Because they're not a good measure of the company's ability to develop products based on the direction from leadership.

Leadership's direction at the time was to use 20% of your time in unstructured exploration and cool ideas like that, though good point of the other poster that that is no longer a policy.