The 6 pro is 0.3" taller and 0.1" wider than the 6. But both are also significantly larger than the previous generation pixels. The Pixel 6 pro for example is 0.8" taller and 0.2" wider than the Pixel 5, which is a significant difference (especially considering you lose the rear fingerprint scanner that gave the ability to swipe down notifications from the unreachable top of the screen).