A WEAK Dollar make IMPORTS expensive (good) and is like a Tariff or tax on people and businesses that buy imports. Encouraging Americans to have it made domestically cheaper.
The problem with China, is the exchange rake is FIXED or RIGGED or CONTRACTED (decades ago behind the scene) to float in a very narrow range so no matter how strong or weak the dollar is, against the Yuan, it can’t do any good. China imports will always be cheaper.