The US and Russian Federation are different countries with significant differences in the amount of diplomatic clout they have access to. Not to mention that unlike China, Ukraine is a significant source of grain, without which there would be a global famine, hence the global pressure to open up the Black Sea.
The US doesn't need to deliberately hit neutral ships, the inevitability of neutral shipping being attacked accidentally by either side will greatly increase insurance premiums, so that commercial shipping is no longer viable. And given that they are fighting an invasion of Taiwan, the US will certainly attempt to block Chinese ports with mines from day one.
The number of ports China will have access to over land bridges will be considerably more limited though. Not to mention the cross-continential railways may not be set up for. Even theoretically neutral European countries for example, will likely cooperate closely with the US, and these are the people that China wants to sell to.
Honestly given how globalised the pre-First World War Edwardian world was, and especially the reluctance of governments to interfere in the market, even during wartime, it's not a bad analogy. When the existence of your country as a great power is at stake, you will become increasingly ruthless.
