Tell me anyone that knows what their tyre pressures are at any moment in time, most folk don't even bother to check tyre pressures.
I recall my ol' Volvo, and a few other cars, it had different recommended pressures for different number of folk on board, did we drive straight to the garage to top up the tyres, no.🤭
I doubt 2 psi less would be a safety risk, I mean, when drag racing I had 10 psi in the rears, I know straight line stuff, but nothing ever happened racing...😉