I’ve mainly used an iPhone 13 and a Pixel 7 pro for comparison, but both have consistently worse cameras than the 6T.
I mostly take close-up photos of plants for iNaturalist, and with both the iPhone and the Pixel i have a very hard time getting it to focus on the right spot long enough to get a good photo. The 6T is much better at maintaining the correct focus IME than either newer phone.
Both the Pixel and the iPhone will frequently try to refocus on something in the background just as I’m framing the shot. I have a third-party camera on the pixel with “manual” focus, but it’s not as easy to use as the OP6T. The iPhone is less bad about random focus changes if i’m taking a picture of a flower in good light, but leaves and stems frequently give me trouble.
I also prefer the color balance on the OP6T to that on the Pixel or iPhone. Much more true to life IMO
Not the 12 afaik