Do remember. All these high crazy display brightness numbers are cool and all but they can take a toll on the battery and cause heat issues for the phone specially if you live in hot countries and that's the reason why you will be able to reach the high numbers only via adaptive brightness. No company will allow it one manual brightness.
This is not a Samsung only case. And other companies are worse as well.
I'd advise against using the screen for too long outside anyway specially in hot sun.
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