Gruber explicitly says that it is fair for Google to compete with Apple and to copy the iPhone. He is making the point that it is reasonable for Apple to compete with Google (in ads).
Here is the excerpt
>>It wasn’t unfair for Google to decide to compete directly against and copy ideas from the iPhone. That’s competition. It may be angering to Apple, but it’s not out of bounds.
>>What’s goofy is the idea that Google would do this — to aggressively change Android from a BlackBerry/Windows Mobile competitor into an iPhone competitor — and that anyone would expect Apple not to retaliate, to instead just sit there and take it and allow all other aspects of their previous buddy-buddy corporate relationship with Google to continue as though nothing had changed.