Apple's "Pro" branding has become increasingly meaningless but in the MacBook category, which I believe is where it originated, it's meant to suggest "media professional", a demographic which has reason to care about all of these things.

There are even shades of this in the iPhone and iPads Pro, which have a few features which are mainly of interest to professional media types. For AirPods it just means "the expensive ones", and for Vision Pro it means "this is expensive". That's the main signal for phones and tablets as well, realistically.