It's ok for that manufacturing to go elsewhere, it's still a huge win for the US in the case in which the conflict with China continues to worsen (likely). It's the ideal approach to dealing with them: drain their economy of its manufacturing & exports and incubate a dollar-caused stagnation as they're unable to transact at the required scale with the rest of the global economy without a massive, endless supply of dollars (the Yuan has a trivial share of global foreign trade). They're already starting to suffocate under the lack of dollars right now, as their current account balance is shifting permanently negative. I'd expect them to begin increasingly restricting their citizens from foreign tourism, as it's a sizable source of dollar bleed, it's a luxury they can't afford much longer. They'll do it under the guise of the need to reinvigorate the Chinese spirit at home and to stop importing negative foreign incorrect values (some party b.s. like that).

It's perfectly fine to redirect all US->China manufacturing into other nations such as Vietnam. Not only is that great for helping other nations develop (many of which are regional competitors of China, so it's further ideal that those nations become stronger vis-a-vis China), it reduces China's position of strength.