This would be true if they listed "alternative store_s_", but what they actually did is add itch.io to their store in a token way once they started the lawsuit in order to say "Look, we have no problem working with other stores". It's a stunt for the lawsuit. Even the Itch founder who signed the deal said they basically found it bemusing and an effort to gain legal leverage without really doing anything else.
It'd be like if Apple took all of the developers who testified against Apple, reduced their commission to 0% in perpetuity, and then asked the judge to throw out their testimony because the complaints were moot.
(That being said, I do think there are conditions where stores would/should allow other stores, and I think those conditions could be more permissive than the Roblox example. Apple should, medium term, resolve the GeForce Now/XCloud objections.)
I bought The Division 2 after seeing a promotion on the Epic store. To install it, you have to install the Ubisoft store Uplay, which is launched through an integration with the Epic store.
After playing that game, I saw promotions for Assassin's Creed Odyssey on Uplay, and purchased it. I later went on to purchase many other games on Uplay.
In short, Epic allows Ubisoft to sell games on its store, for which they presumably pay a cut - for those sales. But Epic has no problems letting Ubisoft require their store be installed for those games, and if you buy something there - even though the Epic Launcher installed it - they don't get a cut.
This is more akin to the App Store installing Fortnite - which Apple could get a cut out of, but not getting a cut for purchases in the app.
Both Apple and Valve (Steam) allow similar arrangements, although not precisely the same. EA games on Steam, and Ubisoft games on Steam before they left Steam, require installing Origin and UPlay respectively. But don't you find it notable that Epic does not distribute Uplay on its own, unbundled from purchases?
On the Apple side, it's ok for applications to require the user make an account on services like Uplay (I believe several Ubisoft games require this; and Fortnite requires the Epic equivalent). You can then use that account to buy stuff on the stores. It's not an exact parallel because there are no (non-jailbreak) external app stores on the iPhone, but it's a close parallel.
It'd be like if Apple took all of the developers who testified against Apple, reduced their commission to 0% in perpetuity, and then asked the judge to throw out their testimony because the complaints were moot.
(That being said, I do think there are conditions where stores would/should allow other stores, and I think those conditions could be more permissive than the Roblox example. Apple should, medium term, resolve the GeForce Now/XCloud objections.)