So the fine seems to be for treating 3rd parties differently from their own stuff.
They could make their own popups require double confirmation instead...
You could argue that choice is questionable because Apple needs to follow its own rules, but also .. it is the Camera app. I think if you don't want the Camera app to use the Camera you probably should not have opened the app at all.
ATT (App Tracking Transparency) is the dialog that says something like "Facebook would like permission to track you across apps and websites owned by other companies. Your data will be used to ... $AppProvidedExcuseHere." with "Allow Tracking" and "Ask App Not To Track" buttons.
ATT is the First consent.
The SECOND consent this case is about is the in-app consent that needs to happen according to French law. I can't give an example of that because I do not live in France but I assume this is probably some horribly designed page inside a French app that asks you to share your data with the ad surveilance industry.
I don't live in france but I'm familiar with the popups. many apps on first install will give you an in-app prompt asking if they can send you push notifications. If you accept, you get the system prompt. if you decline, you don't. I'm not a regulator, but it seems they've misread this one IMO - they only need to provide the conseent at the platform level and can opt out at the platform level if they so wish.