I think the hope of OP was that the rates for shipments from China would go up and the rates for non-China shipments would do down because they wouldn't have to

I think the hope of OP was that the rates for shipments from China would go up and the rates for non-China shipments would do down because they wouldn't have to subsidize the China shipments any more. I countered with the assumption that while the former will happen for sure, the latter won't, but instead the additional revenue coming from the increased shipping costs from China will subsidize higher bonuses for executives rather than be used to lower the costs for non-china packages.