We’ve found evidence in code that suggests the existence of new keyboard shortcuts to change the brightness of the iPad screen or even the backlight of the keyboard. However, we haven’t been able to activate these shortcuts yet, and it’s unclear if these will be customizable.
One of the negatives of the Magic Keyboard designed for the iPas Pro is that there’s no quick way to change the brightness of the backlit keys because the keyboard lacks a function row in an effort to keep it compact.
iPadOS offers an option to remap modifier keys to do things like allow the Caps Lock button to serve as an Escape key, and 9to5Mac suggests that the brightness function keys will be adjustable similar to modifier keys, but with shortcut combinations.
iPad keyboards not designed by Apple that do feature function row keys typically have built-in brightness controls for backlighting, but this would be a welcome change for those that do not such as the Magic Keyboard.