I see this also being a natural psychological thing too. Chinas population is so much greater and there is pride involved in using "Chinese" made just as there is "American Made" here in America. Obviously the user base is throughout the world, but Im sure nationalistic pride plays a large role here. Any time some subject comes up as China overpassed the U.S. in this or that, it's just like okay they have many times greater the population. Now, if they surpass 200 fold in any venue, then that's some other worrisome problem.

Their models are significantly cheaper.

I think this explains their popularity more so than population differences. National pride is OK but most people won't pay significantly more than necessary just to express it.