The noise inside a helmet at highway speed is very high - say 90-100 Db without ear plugs.
That kind of noise level is very hard to cancel out, and to boot it's the low freqency stuff from buffeting and vibration that bothers us the most. And unfortunately that low-freqency noise is even harder to cancel out
Noise in the higher spectrum is more easily filtered with earplugs and so present less of a problem.
Overall a noise cancelling helmet is a very different proposition than trying to filter out a constant background hiss in and airplane which is what most NC-headsets are made for.
If you want a quiet ride the best solution I've found over the years is to have clean airflow to your helmet (no screen), a really good racing or touring helmet and then a really good pair of earplugs.