I am still surprise that the Carry on Depth they allow is 8 inches only and not the standard 9" or even 10" as other Airlines do.
But they allow (22" x 16") for being Tall and Wide which is more then enough.

Do they Strictly enforce 8" inch Depth on International flights like A330-neo and even A321..
All my carry on are 9 or 10 inches in depth and hard shell with Rollers.