Rollouts are not made to boil frogs, they are made so that you can test the impact of changes, and crucially, quickly roll undesired changes back. It’s a great technique. This is important when you’re at Google-scale - any small mistakes will impact millions of people. The only realistic way to handle this is to roll changes out and monitor the changes for negative impacts - stuff like crashes and so on.
I agree that what they’re doing is boiling the frog, but rollouts have nothing to do with it.