My experience is that there is minimal noise on P4P, Mavic Air, or Mavic 2 Pro/Zoom at ISO 400. Motion blur is catastrophic for accuracy and quality while a little more noise has very little negative effect in reconstruction. In the UK the light is so poor in the winter that increasing ISO is pretty much required unless you want to fly very slowly.
This map was the Mavic Air at ISO 1600 (!), you can see the noise, but compared to the blurry mess at ISO100 I think it’s well worth the tradeoff. (Check out the 3D model to see what houses in England look like!)