I'm 6'0" and I complained to Tesla about this last year, wondering whether our vehicle's belt had an unwanted half-twist in it. Service Center determined ours was no different from any other vehicle, so nothing was changed. The belt would, I believe, have to be altered at the base, spring winder level, with that element being turned 180º...and that is more than a ten-minute procedure.
It frustrates me to the extent that about 1/4-1/3 of the time that I'm driving, I give it the desired half-twist myself up at the shoulder, which then makes for an unwanted, unstable, and probably dangerous-in-a-crash half twist right at my belly.
I don't understand it. Providing that half-twist allows the belt to lay flat against the upper torso-neck area - it must be a safer, more natural attitude. I have been awaiting another's input into this situation to provide my own experience, so I thank the OP for initiating this thread.