I have to say this is an insane fear that does not reflect the world as is, or if it where true, it would have terrible implications.

First of all, China and the US, besides their rivalry, are huge economic partners: china and the US trade from each other a lot. Either of them going into military conflict with the other would mean massive economic losses. Im not saying it cant happen, but it cannot be the goal to get richer so in the end you can get poorer.

Ofc is reasonable to think that being an economic power gives you also political power, and as an American you can perceive that the US benefits from that position today and doesnt want to lose it to China.

I would say that first of all, most of U.S. intervention in other countries has cost dearly both for the intervened countries and to the american taxpayer(and sometimes citizen or soldier). China as well as the US are a problem in that regard. Its true that it could have negative consequences, as it does for the US to have that power, but it feels to me secondary to economic power, and more relevant to how international institutions should work.

In any case, China doesnt have to surpass the US to do this, as today it already has a lot of questionable policies(like being an ally to north korea, or getting into borderline military conflicts for sea territory).