I'm not him, but I'll give you 10 (in no order other than what comes to mind first):
The gross mistreatment of the Uighur ethnic/religious minorities, which basically has placed their population centers under martial law, and effectively bars their religious practice outright.
The "Great Firewall", a giant internet censorship engine that blocks any discussion that might be critical of the Communist Party's domination of China. People here complain about net neutrality, but what's done by the Chinese government makes NN look like a non-issue. Interestingly, as abhorrent as the internet censorship is, the medium is still considered less heavily stifled than other forms of communication in China.
The elimination of democracy in Hong Kong. Despite prior commitments to a "one country two systems" governance of the former British colony in all matters other than foreign affairs and national defense, the democratic features and personal liberties enjoyed by the city are rapidly being swept away, including brutal crackdown on pro-democracy assemblies and protests.
China continues to prop up the Kim regime in the People's Republic of North Korea, one of the worst human rights offenders in the last 100 years. I'd make a list for what Pyongyang does, but I'd be here all day.
China continues to blatantly ignore (or in some cases, encourage) industrial practices that ignore intellectual property laws of foreign nations, which costs the US over $50 billion a year (you could employ one million people at a salary $50,000 each for that much money, so basically China steals an entire large city's worth of productivity from the United States).
China also ignores consumer safety requirements, and even basic health concerns both internally and abroad, for the sake of profit. When the US began to test more carefully for lead in toys, a number of Chinese firms switched to Cadmium, a far more toxic substance, rather than electing to just produce toys that don't poison children. This kind of behavior is condoned there. Products from China in particular frequently assert compliance with safety laws that they do not meet at all (think those hoverboards).
The continued expansion of artificial islands into the South China/West Philippines Sea into foreign waters, despite repeated warnings from other nations and in violation of international rulings by the UN Convention on Law of the Sea, and at great expense to the local coral reefs and general marine environment.
Suppression of religious liberties. Christians, as well as any lawyers who try to counsel them, face increased crackdown on their religious practices, including the demolition of churches for vague "zoning violations" and frequently arresting the church members for speaking out against the removal. If you are not a member of the 5 state-recognized religions, treatment is even worse than that.
Tibet.
The imprisonment, "disappearance", or torture of human rights writers, lawyers, and academics, who criticize the government of the above 9 or any of the many other examples total disregard the leaders of the People's Republic of China have for even basic human rights.
You will note I kept this current. If you were willing to go back 60 years, you could include Tiananmen square, the One-Child-Only policy, and the Great Leap Forward, which killed 60 million people, making China several times worse than Hitler and Stalin combined.