I actually think it is a textbook apology - short, no excuses and straight to the customers. I think having a quick apology is more important than presenting some kind of ten point plan as the first step.
But I agree that the end of the matter is the solution, not the apology, and we have yet to see how this ends.
If Bezos wanted to fuck around with his apology, he'd have used more cushiony words. "Stupid, thoughtless, and painfully out of line with our principles" doesn't allow for much leeway with how he views Amazon's actions here. He's saying straight out that they made a mistake.
But I agree that the end of the matter is the solution, not the apology, and we have yet to see how this ends.