I've parked several times today with the front close to an obstruction & driven slowly as far as I believe I can without making contact. Each time the coloured orange-red line was accompanied by warnings of 13" - 15" and the car was actually about 10" away when I checked. I am confident that I can park accurately without needing a warning but the on-screen messaging has been more accurate than it used to be, albeit each instance today was towards other cars, walls or a hedge, ie solid & with reasonable height.
Rear parking shows a more stable white-orange-red line than it used to and a better approximation of the shape of the surroundings (I almost always reverse to park).
Maybe update 2023.26.1 includes some slight refinement although I am still ignoring it & will continue to park without using the ussless guidance.