Calls for violence is indeed against the law in the US, overt racism is against the law in some countries so global companies must adhere if they want to operate there, at least blocking it in those countries.
The problem is also how do you define what is racist, what is just facts and what is just blocked because of political reasons. That's why the American constitution approach is much better on that issue. Calls for violence on the other hand is much easier to define.
I wish all those tech companies would just define their policy as whatever is legal is ok, they are too big and more like an essential platform like electricity or water monopolies. You don't want a phone company to create their own guide lines about the content in their network as if they are some private club with its own rules.