Would you feel as strongly about this if it was a corporation, instead of a single individual?
If I as corporation buy from a third party OEM and they decide to move production from Texas to Malaysia or Vietnam, would you also feel strongly that I as customer am entitled to a discount?
Or would you consider that we have agreed to a contract where the supplier is delivering the same OEM product but now from a different location?
If a supplier changes locations I would definitely expect prices to change in future contracts. Of course the current contract shouldn't be changed if we had already agreed on a price for some number of units.
The OEM is selling a tradable, so you would expect companies to already search the world for the cheapest version and be buying that, as there is effectively a single global market.
Labor, historically, has not been so mobile. There is not a single market for labor, there are many different markets.
And in each market, the company pays the prevailing market wage. For that reason, when someone moves from market A to market B, their wages are adjusted up or down based on the cost of labor in those markets.
Just wait till Google realizes they can hire equally competent people overseas for a fraction of the wages and those people won't have any of the cancel culture tantrums American workers do.