first of all, it was not zillion of dollar but billions. Second, i think you underestimated two things, the complexity of the HS tech, and the problems with China star. Even in the article it said that China star has glitches and high operational cost, and signigicant gap with the foreign made ones. I didn't say that China can't solve it, but how long and how much money will be wasted before the problem can be solved and catch up with the foreign HS train? Nobody can answer that.
It is just like how the Chinese pursuing the jet engine tech. It took a long time, and god know how much money have been wasted, and even know still has some problem. I'm sure if China could buy the tech, China would have gone that way in the beginning.