As much as I would love that to happen for the sake of Bitcoin, I doubt they will go that route. These things are a little more complicated than this. They will also consider how it will affect them negatively. I doubt they will want to hurt themselves just to hurt the US.
However, whatever the economic situation on the global markets, I would not agree that China will just decide to invest in BTC, given that they are fanatics who are obsessed with control, and how will they control something that is decentralized and also largely depends on mining farms and various companies located in the US?
I don't think this is a reason that will make them not sell their treasury holdings off and go into bitcoin and gold. Yeah, I agree that they're obsessed with control (so is almost every other government), but in this case, they're not trying to control Bitcoin. They just investing. I mean, they don't control gold too ,but they can invest in it.