One thing that wasn't mentioned is the max sustained screen brightness for SDR, which is higher on the M4 Pro (1000 nits) compared to the M4 Air or M1 Pro (500 nits).
There’s an awesome app called Vivid which just opens the HDR max brightness. I use it all the time with my M3 Pro when working outside and I believe it also works on earlier models.
There are so many base features that are inexplicably relegated to 3rd party apps. Like a better finder experience. Or keeping screen on. Or NTFS writing.
What's crazy is that Vivid app...costs money!