I don't know exactly when you last tested 7 series' PC Mode, but HDR Standard in PC Mode with proper settings and temperature has no accuracy or color issues at all, as it can be basically identical to calibrated HDR Technicolor Expert with Active HDR (just even brighter, and with slightly more highlights clipping on 4.000 nits and above contents), with also low input lag.
Not for a good while, I just know what it was like, but if that is indeed possible to get it accurate without pro calibration, then that's good.