There’s nearly a century of NFL QBs playing with underinflated footballs multiple times a season. Nobody noticed, nor cared.
The difference you are seeing, is when the pressure is different by 2 PSI in room temperature footballs, when the QBs have a chance to stand and knead the clean dry footballs with another football for immediate comparison - something they don’t do during the games.
Every one of those QBs who claimed they could tell each played games where the footballs were down by at least as much pressure as the lowest-pressure football in the 2014 AFCCG - with Mark Brunell in particular playing the equivalent of nearly a full season of such games, despite playing in Jacksonville in a southern division.
Most prominent QBs played games where the footballs were over 3 PSI low, and didn’t notice. And this is without the additional effects of rain. This is a normal phenomenon.