I wear my AirPods Pro on the train largely for hearing protection. The DC Metro is loud, with or without people making noise in the train. Different train systems have different levels of loud, but when the Metro is flying through a tunnel it is quite loud.

I also often have them in while walking around the city for this purpose as well. I usually have the noise canceling off, but if an ambulance or something is coming my way, I quickly click the AirPod to put them into noise canceling mode.