It's been an issue since several years ago, or maybe longer as Wikipedia suggests. Last year when I was taking LP380 I discussed this problem with Prof. Ellan, a democrat. As most left-wing Americans would recognize such an issue and blame it on racism, it's not within their power to solve it. There are way more people holding different options, no matter holding themselves as racist or not.
How do you know a country if you have never been to or know any of its people? You listen to the media.
How does a medium describe a country? They describe it the way however people like it, especially those people with the highest bid. Bias has always been a problem with media and there are even businesses measuring this, like adfontesmedia.
The problem is, no matter how biased a medium could be, they are good at talking people into believing them. It is simply their job.
Many boasts free media to be one of the base stones of democracy, well it is part of the truth. The part it doesn't mention is that media can be easily manipulated by the few in power, aka the highest bidder. With little tweaks, the whole public opinions could be redirected, then magnified.
It turns out, media under democratic government master such skill much better than others, as those counterparts from under authoritarian governments grow in a much less competitive environment. Instead of propaganda, they could use censorship to achieve the same effect to divert public opinions, which would not work in a democratic system.
Now we conclude that it is the media propaganda that does the most to promote anti-Chinese sentiment, we would be talking about the motivation of those highest bidders behind, who benefit the most from such public sentiment.
The fact that China can achieve greater success in economical development, scientific progress, pandemic containment could cause problems for the entire modern democratic system as China is not one of them. An ideology debate would strike at the foundation of the lawful state of the modern democratic governing model, aka the cold war.
Normally there would be no such problem. But when caught in trouble, i.e. an economical crisis, a failed pandemic containment, when people remember to blame the government, such comparison could be fatal. USSR collapsed after proven inferior to the modern democratic governing model, and the same worst thing could happen to the other side too if proven otherwise.
And the best solution is to redirect the public opinions of China so that nobody would give it a shit.
Response of Chinese government
The Chinese government seems rather dull in such anti-Chinese sentiment, and are producing more excuses to be blamed on such as human rights issue in Hong Kong, Sinkiang, Inner Mongolia, and border disputes with India, Southeast Asia, Japan.
The motivation behind the Chinese government is simple: the Supreme Unification, which is the traditional base stone of the lawful state of the Chinese government. It is a concept not just about territory integrity, but about the universal standards of every aspect of people's life.
车同轨，书同文，行同伦。 Standardized transportation system, single written language, and consensus on moral/ethical standards.
This could explain nearly all the problems, just not as modern democracy expected. It is generally regarded as an infringement on human rights by modern democratic standards.
One explanation could be that the Chinese government expected nobody would care when it pushes its policy on internal affairs especially when other countries are in the middle of both economical crises and failed pandemic containment. Well, 20 years ago it might be true as China was not mighty enough to catch world attention, and the time has changed.
Response of Chinese people
Nationalism ensures Chinese people that the greater pressure from the outside world, the more supportive they are of the Chinese government, and more isolated from mainstream modern democracy this time.
Many believe that Chinese people don't agree with their government and expect the Chinese to rise up against its government, which would not be the case as long as the nationalism is still prevailing. Historical invasions from modern democracy government to rip Chinese territory apart results in such nationalism, and they are still trying as many Chinese would argue, i.e. Hong Kong, Sinkiang, Tibet, Taiwan.
In the end, propaganda to teach people to express anti-Chinese sentiment was never intended for Chinese people to rise up against their government, as it is just a tool to strengthen unification on the other side, based on sentiment against a common enemy.
One true enemy for propaganda is the ability of critical thinking, which would be the common enemy of both modern democracy and authoritarian government. A large group of people with critical thinking ability are difficult to be manipulated by propaganda and would demand democracy for themselves as they cannot always reach consensus voluntarily.
The question is, are (almost) all the people able to have the ability of critical thinking through education, and how long would it take for the general public to reach that stage. Before then, racism, bias, propaganda, manipulation, authoritarianism would remain problems.