I just got the AirPods Pro 2 and based on my 20 minutes of listening during transit in the train, walking besides the road and in a quiet room, yes the noise cancellation is more impressive than the 1st gen. For example, I can still hear a little noise from a running air-conditioning on the 1st gen but totally quiet on the 2nd gen. Love the adaptive transparency feature too. The sound is a little better, especially on the bass response where they are tighter and more pronounces. Overall, it is indeed an improvement over the 1st gen.

I'm using iPhone 14 Pro Max, which is supporting Bluetooth 5.3. I'm not sure if there will be any noticeable differences if paired with a iPhone that only support Bluetooth 5.0 and below. Also, there is no mentioned of Apple enabling or using LE Audio during the AirPods Pro 2022 keynote. Maybe it will be a future feature but as of now, I believe there is no differences.