This title is complete bs, and the court ruling (linked in the article) only mentions monopsony very briefly.
The question addressed by the court is regarding who is the cause of any overcharging to the customer. The opinion argues that because Apple is exclusively dealing with the customer, it is able to sell on whatever terms it wants to the customer, so any overcharge is their fault. The dissent argues that because the developer has the power to dictate the price of the app on the store, any overcharge the customer pays is directly caused by the developer, because the developer could have chosen to sell the app at a fair price.
It is true that the ruling mentions that developers may sue apple, but that was never in question. Both the opinion and dissent agree on that fact.
This is an unfair treatment of the decision. The question addressed by the court isn’t “who is the cause of supracompetitive prices?” but rather “if Apple is the cause, can consumers sue?”
Apple’s defense argued that only the app developers could sue under a certain view of the precedent where Apple’s role as a pass through is essentially transparent to the law. Their argument attempted to shift who the customer was ultimately doing business with: Apple or the app developer.
One of the theories underpinning the precedential rule is that not stopping impacted downstream parties from suing may potentially subject Apple to multiple liability. Apple argued that they were already liable to app developers so shouldn’t also be liable to consumers. The Court is saying here that that theory does not hold water because Apple, as a middleman, may be liable to both upstream and downstream parties (damages from app developers and consumers, respectively).
Off topic: I like your nickname. In that vein, here are two variations of the same sequence of keypresses shifted up and down respectivelly: "erweriotuout" and "cvxcv,.bm.mb".
While something like "4694372" is motorically meaningful to a person typing it on the keypad, or to someone watching him do it, it translates to the screen space as gibberish. Another way to put it is that when typed it has an obvious structure, but when read on the screen, the structure is prohibitively difficult to discern. That's interesting, because it's all too easy to forget that the computer as we know it today can interface with only a very small portion of our faculties.
The question addressed by the court is regarding who is the cause of any overcharging to the customer. The opinion argues that because Apple is exclusively dealing with the customer, it is able to sell on whatever terms it wants to the customer, so any overcharge is their fault. The dissent argues that because the developer has the power to dictate the price of the app on the store, any overcharge the customer pays is directly caused by the developer, because the developer could have chosen to sell the app at a fair price.
It is true that the ruling mentions that developers may sue apple, but that was never in question. Both the opinion and dissent agree on that fact.