True, they requested that Red Dawn be re-edited, so that China was not the bad guy. I have not seen the movie, nor do I care to.
However, let's think about this situation for a moment, as rational adults. And if you can, then try to think about this from the other side.
There is a lot of bad blood coming out of American media about China. It's in the news, the movies, the TV shows, the literature, it's everywhere. Unless you are dense, then I think this can be established as a fact. China is continually being painted as the big bad scary commie, that's out to eat your children (or something like that), or at least, they're taking your iPhone assembling slavery jobs.
A movie like this, would add more fuel to the fire. You, as an intelligent individual may be able to distinguish that Red Dawn is a fictional movie, with good and bad guys. And this sells tickets. And Americans love this! They want a big bad evil enemy, that their country can destroy. And right now, China is it!
However, can you guarantee that another American, of lesser educational intelligence than yourself, can distinguish such a thing? That this is pure fiction, and not a proxy of reality.
Nobody wants to be painted as the bad guy. Americans movies will certainly never paint America as the bad guy, despite the fact that millions have died at the receiving end of American weapons. In fact, I can't recall any media where America is painted as the bad guy.
The Chinese people certainly don't want to see themselves as the bad guys. Especially not when it's a historical fact, that they have been severely dominated by Western nations. And hundreds of millions of their people have suffered and died. And to this day, there are certain white people, that are proud of what their race did to China in the 1800s. And if you find this shocking, please let me know. You can find this perception all over the internet, and you can poll your close friends, and ask them what they truly think.
Anyways, movies are political statements. When you make it too real, then it hits too close to home. And there are certain dangers with that kind of propaganda. And it will certainly upset the people on the receiving end of it.
Stick to making movies about aliens and their probing devices, zombies, and superheros in tights. Or killing the evil German Nazis. Nobody will question these kinds of movies.