Protectionism in general is bad. But it's not protectionism to want to limit or stop trade with serious privacy and security consequences from a clearly hostile state. Letting Chinese EV's flood our streets when there's no realistic way to know what electronics they really have in them is insane.
Same goes for all electronics of course. But cars are particularly dangerous as we rely on them so much for life. Imagine the chaos if in a lead up to a war, China disables (or intentionally crashes) every overseas EV in western countries.