Chosen Solution
I recently replaced the display on my MacBook Pro after it having cracked. After the replacement I have no more auto brightness and the True Tone option is now gone. In System Profiler under Displays, it shows as a built-in Retina display and Auto Brightness says “No”.
I’m not sure how Macs will behave, but judging by Apple’s recent repair policies, this is normal. Screen repair needs to be Christened by Apple to retain these features, even if you take two brand new Macs purchased from Apple Store and swap the screens.
This has nothing to do with Apple. If you exchange the Display (current state as of 07/26/20), it will directly work, no magic needed. What will (mostly) not work is the auto brightness and True Tone, but this belongs to the new display and is totally HW related, as for most of those 3rd party display, the needed sensor is missing or failing, that is why you get them rather cheap. I bought three different display, all suppliers (China, UK) stated it would be original, which they were not. I ended up with an original one from Apple, everything worked well, it worked instantly after exchange without using any tool/calibration.
