That is way too much weight for a new vehicle; tyres, etc. and I bet that Pirelli tyre is well ‘out of round’. (I’ve always found Pirelli tyres to be the absolute worst in this regard).
Demand a ‘Road Force balance’ on a top of the line Hunter machine and look at the runout of both the wheel and tyre. If the wheel is fine but the tyre is badly out of round have the tyre rotated on the wheel until it’s as balanced as possible with the lowest amount of weight. If it is still difficult to balance it should be replaced by the closest Pirelli dealer.
As for pulling to one side: that is from a poor alignment and Rivian needs to fix it.