That's a pretty huge difference in terms of modal share.
And even with the sprawling size of the US network (and differences in things like labor costs), US freight rail is still more efficient at moving cargo in terms of costs.
Now do comparison of transporting people and that’s impact on the economy
China:
Total length: 155,000 km (100,000 km electrified)
Total passenger/km: (1,470.66 billion passenger-kilometres, 2019)
Total freight: 3,018 billion cargo tonne-kilometres (2019)
US:
Total length: 257,722 km (160,141 mi) (I can't find figures on electrified length, seems at most 2000km?)
Total passenger/km: (10.3 billion, 2014)
Total freight: 1.71 trillion short ton-mile, approx 963 billion tonne-kilometres (I used wolfram alpha for that conversion)
So if my calculations are correct - which they may not be - on fewer rails China transports an order of magnitude more passenger and freight traffic.
But the premise is meaningless. It's easy for a government to affect the usage of something by subsidizing it or constraining alternatives to it, which has little to do with whether it would be more efficient or well-managed as a public agency.