Is there a way to get Auto-Brightness back on my iPhone X? One of the best features of my iPhone 7 Plus was the way it could be configured to auto-dim the display, which not only helped the phone's lighting to match the mood, but was also appreciated by people around me in dim environments (trains, planes, cozy cafes, etc.):

 

My iPhone X adds a neat feature that adjusts the tone of the display to ambient lighting to keep it consistent, but this does not (at least not sufficiently) adjust the brightness:



As a result, the phone is always far too bright in dim environments (and often just a tad to dim in bright ones). 

In my experience with macOS, there tend to be advanced or hidden settings preserved for features that Apple has removed from the UI. Is this the case with Auto-Brightness? Is there some way to get the auto dimming behavior back on my iPhone X?
Yup, hidden settings it is! Since iOS 11 Auto-Brightness has been moved to Display Accommodations.

1.) Launch Settings app

2.) Tap General

3.) Tap Accessibility

4.) Tap Display Accommodations and toggle on Auto-Brightness