Im on my third pair of Airpods pro (replacement courtesy of Apple) and all of them had the ANC partially fail the longer i use them. I wonder why Apple still release new versions of these whem they cant even get the basics right.
Cheap foam eartips from Amazon are even better than stock for my AirPods Pro but they need to be replaced more often.
In any case these workarounds are moot, because my $20 Chinese ANC earphones work (until today) without all these fussing around at all.
I hesitate to share an Amazon link but it might help rescue your investment if you still have them: https://www.amazon.com/gp/aw/d/B0G16F5VVP