Which is why "better than existing macbook pros" isn't a selling point. It's already more than good enough.
The parent comment was saying "better sound" as one of the upgrades you get for the $400, which is a comparison to the currently available macbook pros.
Call me old fashioned, but I think "this one is even better than the last one, and you already liked that one, so imagine how you're gonna enjoy this one", is indeed a selling point. It's one of the most common and enduring selling points.
The parent comment was saying "better sound" as one of the upgrades you get for the $400, which is a comparison to the currently available macbook pros.