I don’t care how they do it but I want to be able to press and hold the flashlight icon and, without lifting my finger, immediately begin to slide my finger up and down to adjust flashlight brightness.
Boo form over function. Very minor nod to the increased granularity.
IMHO, the problem isn't the width adjustment, it's that the control is now small and you have to change your grip to reach it. Apple could just added the left / right width swipes to a large full screen UI.
(Also worth noting, only recent Pro iPhones can control beam width. Left / Right beam width control is disabled for not-pro phones but the UI is still the same clunky Dynamic Island thing)