When a spec sheet says "up to 38 dB of cancellation", that number almost always describes the best possible case: a constant, low-frequency tone measured in an anechoic chamber. It is a real figure, but it is not the one you will experience on a bus at seven in the morning.
Three scenarios, not one
We measure every model in three reconstructed environments: public transport, open-plan office, and a street with traffic. Each one punishes a different range. Transport concentrates energy below 200 Hz, where active cancellation works best. The open-plan office is dominated by human speech, between 300 Hz and 3 kHz, which is exactly where any active system performs worst.
The seal matters more than the electronics
In our measurements, switching to a correctly sized ear tip improves perceived attenuation more than moving up a tier of active processing. That is why Buds Pro ship with four tip sizes in the box: it is the cheapest and most effective way to improve the outcome.