I think it's debatable whether torque vectoring is pointless on a 2-tonne SUV, but I would argue that it's pointless on all 4WD vehicles.
The diffs in a 4WD system can usually only transfer a set amount of torque by design from side-to-side or front-to-back.
PTV+ or brake torque vectoring is used to effectively enhance the effect of the torque transfer in a positive way by braking a wheel (usually the opposite inside one).
At least that's my understanding.
FWIW my 2022 GTS has PTV+ and 'handles' way better than my 2019 S without PTS+ did, but then that's a bit like comparing apples to pears....
Chris.