I believe this is possible but unlikely. I don't think a Chinese company trying to break down the US's stronghold in this field would do this short term. I think it is in their best interest to be cheaper, better, easier, and more trust worthy until competition looks silly.
It's like suggesting BYD has a high likelihood of making their cars into weapons or something. It's not in the company or their countries interest to do that.
Sure it could happen but I bet it would only happen in a targeted way. Why risk all credibility right now and engage in cyber warfare?
Need the "why not both?" meme here.
BYD and Tesla have the same ability to brick their cars anywhere. It's less a "weapon" and more a way to cripple a subset of people overnight if they so choose. A general major downside of "connected" products.