Confirm this problem exists on a MacBook Pro 2017 13" i5 (a1706) with touchbar. Have tried SMC reset, PRAM reset. Even reformat and re-install Monterey and same issue. No brightness control in display, Touchbar brightness control shows on screen graphic but no effect to brightness. Have tried Reboot, boot in to safe mode, and changing user. Also changing scaling and color prefs still no control on brightness. I am a Computer tech of 40 years. Bought this MBP 2nd hand at a bargain price due to flexgate. Have replaced display. System is configured as a Dual boot with Mojave and Monterey. Booting in to Mojave no issues brightness control work as it should. But in Monterey, nothing. Brightness is up full and it drains battery very quickly. Have raised a ticket with Apple support as this should not be happening. It maybe due to the display being changed but this would not explain why everything runs fine in Mojave. Definitely something is up with OS.