It works perfectly for me - and definitely better than the XM4 or XM3 I tried.
Almost nothing can be heard in the aircraft.

there is a difference but if there are no loud sounds you won't notice a difference but if you set it up in the app it's like a pamir tip set it to off without music and nois canncling without music you will notice the difference

had exactly the same problem, no difference between off and ANC

I've had exactly the same problem with my linkbuds S since they came back from repair.
The ANC works well on the right one, but it seems to be virtually non-existent on the left one, which is unpleasant to use.

Hello, I am also totally dissatisfied with the ANC of these expensive Sony headphones. There is simply no difference between the OFF mode and the NOISE REDUCTION mode. Sertronics and Sony deny everything - really bad!

Hello,

Have you found a solution?
I have the same problem.

Same here...

Hello, same disappointment for me, no difference between noise reduction on or off.

Hello, I agree. The worst ANC I have ever (not) experienced. It is de facto non-existent. And it gets even worse: if you leave the supposed ANC on a low setting, it even cancels out the damping effect of the silicone plugs. The headphones are not even able to filter out monotonous noise, e.g. on an aeroplane.