AirPods Pro are in ear, they compound the issue of earwax on your outer ear into a worse problem. That's according to me ear doctor, feel free to argue further with me but that's what he said.
I think it's more a case of constant ear bud usage packing in the wax and concentrating it. It got so bad for me, even the water tool they have at my doctor's office didn't work to remove it.
Doctor said he sees this all the time, and ear buds are to blame.