That's an excuse and it's not true.
I don't know if you've followed the history of Chinese eminent domain, but it turns out their society is extremely legalistic (always has been really). They have to buy out "holdouts" the same way we do in the US. Single houses will delay construction of projects for years. (The HSR just put viaducts OVER them in some cases.)
The big thing is that they have one political party which is all in on building HSR; they don't have a bunch of cadres and apparatchiks saying "rail is stupid, we should build more highways instead". That's the difference. (In authoritarian dictatorships where they DO have that -- and there are some! -- they are not building HSR either.)
On other issues, like getting rid of coal and establishing solar & wind power everywhere, there IS dissent among the ranks of the CCP officials, and as a result that has been going a lot slower and with backsliding. The big thing is that in China, *nobody is actually AGAINST passenger rail*, unlike here.
France, Spain, Morocco, Taiwan, Japan have all built HSR. Democracies, monarchies, dictatorships, the big difference is that they didn't have organized, powerful *rail-hating* groups. We do. So do several South American authoritarian countries which have failed to build HSR.