> Premium mediocre is Starbucks’ [...] original pumpkin spice lattes featuring a staggering absence of pumpkin in the preparation.

It is confusing, but "pumpkin spice" is the name of the traditional blend of spices used in pumpkin pie. It's like how "salad dressing" doesn't contain any salad.

Definitely. The "premium mediocre" stuff has been on my mind a lot, and I'm sure it's conceptually related. "Downward mobility" is a good term here.