CPU & GPU Throttling and Screen dimming

Why apple use that bad feature for iphones?

I buy new Xr, I downloaded the pubg, i set the settings to max, i set the brightness to max, i was thinking now i will play in pubg! After playing 10 minutes, my XR have a lot of throttling and the brightess goes down and i was not be able to see normaly in game and i died🤷🏻‍♂️🤷🏻‍♂️🤷🏻‍♂️ When i edit the dng file in lightroom, i have the same issue! Brightness goes down and I can’t edit my photos🤦🏻‍♂️🤦🏻‍♂️🤦🏻‍♂️