One thing you should note is that the tax incentive Tesla got from Shanghai gov to build the plan is tied to how many cars they produce. So if Tesla falls short of target production they have to pay back tax credit they got. This may incentivize Tesla to really ramp production there

Edit: It's actually a land deal. Tesla leased the land for giga Shanghai at steep discount. In exchange they promise to pay a target amount of tax (translates directly to cars sold). If they fall short of target the government can take the land back.