If you want difficulty, you can crack Leetcode in your freshman year in China.
In my opinion, the real advantage of doing undergraduate in U.S or Canada is enculturation. You can't possibly do it anywhere in China. Eventually, Chinese in North America struggle with language barrier, cultural difference and identity much more than academic excellence and coding experience.
But is enculturation necessarily a good thing? It depends. If you plan to go back to China, being encultured(more likely, partly encultured) into American way will probably only hurt you.