More anecdotes! I use the AirPod Pros many hours a day and have mild tinnitus. I find the noise canceling makes me more aware of the singing in my ears. I don't live in a place where silence happens, but the cancelling will kill the outside noise enough for me to remember that the ears are always singing to themselves.

For people experiencing loud noises, be aware that if the microphones can come loose, then they can get weird transients from vibration, shock, or even the sound being driven through the AirPods. The original AirPods were subject to that, I had mine replaced once and when they came loose again stopped using them. (Gross note: the original ones made me more subject to disgusting things happening best left unmentioned when used many hours a day. That was most of the reason for not getting them replaced again. The new ones definitely breathe better and don't cause me trouble.)