This is not a free speech issue. This is not a censorship issue. This is companies deciding that they will not do business with some parties. Those parties nor the reasons and the actions of the companies today do not fit inside narrow definitions which would make what anyone did today unlawful.

Moreover 8chan posts, though vile, arguably do not fit the narrow free speech exemptions of the US such as true threat or incitement. The law and judicial precedent would require a reasonable reader to take it seriously. All that is moot though as the government has taken no action here.