You're actually linking to the old policy, the new one is here and will go into effect in March: http://www.google.com/policies/privacy/preview/

It's actually longer than the "existing" policy, but covers a lot more of Google's services under one umbrella.

In any case, a TOS is basically governed by ordinary contract law, which allows for a much more generalized, principles-based document.

Privacy policies are increasingly governed by regulatory requirements, and those requirements are increasingly demanding a fair bit of specificity, so you're seeing an inevitable and likely permanent state of affairs.