Don't have a pixel, would like one, but it's been my experience that movement is the trigger tied to the proximity sensor. I've have phones with this feature and with phone in shirt pocket , I bend over and phone turns on when I straighten back up. Stays on till screen timeout setting is reached. Was annoying and putting phone in shirt pocket upside down solved the problem. Now when in pants pocket it's a different story, sitting, then standing phone is on. Maybe Google has this nailed better. If it's tied to the sensor which I would think it has to be then then yes, it will turn on whenever the motion is achieved. How long it stays on would depend on other settings like lock screen timeout. I prefer double tap for this reason and the pixel now has that option. Raise to wake is the most useful for me when sleeping and I want a quick time check, but double tap works nice as well.