Earlier quoted context omitted.
Noise cancelling only really works for constant sounds (like airplane engines), not for background music/chatter.
Why is that btw? When I first heard of noise cancelling a few years ago, I figured electrons travel faster than sound waves (by a few orders of magnitude), so they'd just have a mic on the outside and speakers on the inside, amplifier in between and connect plus and minus the wrong way around to create an inverse signal. No chips with delay needed, just an analog signal going directly from mic to speaker. Shouldn't t…
But I will say my sony wf-1000xm3 do seem to do a pretty decent job muffling most noises.