Does it matter if an attacker can decrypt public wifi traffic? You already have to assume the most likely adversary (e.g. the most likely to sell your information) is the entity running the free wifi, and they can already see everything.
> You already have to assume the most likely adversary is the entity running the free wifi
why do you have to assume that?
you're at Acme Coffeeshop. their wifi password is "greatcoffee" and it's printed next to the cash register where all customers can see it.
with WPA2 you have to consider N possible adversaries - Acme Coffee themselves, as well as every single other person at the coffeeshop.
...and also anyone else within signal range of their AP. maybe I live in an apartment above the coffeeshop, and think "lol it'd be fun to collect all that traffic and see if any of it is unencrypted".
with WPA3 you only have to consider the single possible adversary, the coffeeshop themselves.
It is precisely because the operator of the wifi is not necessarily the adversary a user may be most concerned about. They may be, but they are not the only one. They are the one you know can be, but they aren't the only one.