The iPhone 12 had consistently died on me after about 12 hours off the charger every day for the past week. Needless to say, I wouldn't suggest it to anyone that needs solid battery life. It seems worse than the Pixel 4 XL, but somehow it isn't getting the flack the Pixel 4 did.
He doesn’t mean screen on time. He just means from taking it off the charger to the phone dying which means the SOT is somewhere in the ballpark of around 5-6 hours. Phones have been released that lasts more than a day off charger