Their is quite a political bent to it. In essence, anything against their ideology will get censored and get users banned. Any anti China or anti Russian state sentiment is enough and is categorised as racism/orientalism. See the below posts for further explanation and examples.
lemmy.ml might choose to censor or ban anti-China sentiment but other servers don't have to. They can do whatever they want. There are hundreds of servers to choose from - that's the whole point of a federated system!
Besides, Reddit has an extremely strong anti-China sentiment because its readers are too stupid to have nuanced opinions deeper than "CHINA BAD". It was getting kind of scary how much it felt like propaganda. So lemmy.ml decided to ban xenophobic discussion of any kind to avoid that kind of influence.
[0]https://lemmy.pineapplemachine.com/post/5781
[1]https://mstdn.social/@feditips/106835057054633379