The United States abolished slavery later than most other Western countries, including the British Empire, and at its founding was "free" only for a minority of white, land-owning males. While the Bill of Rights protected local elites from dictates of the federal government, it was not applied to state governments until the 20th century. State-level blasphemy laws were applied up until the 1930s: https://en.wikipedia.org/wiki/Blasphemy_law_in_the_United_St.... Additionally, free speech was applied highly unevenly throughout the 20th century. The 1960-70s liberation movements that gave us most of our substantive freedoms were fought viciously by the US government, with methods that went as far as assassination: https://en.wikipedia.org/wiki/COINTELPRO.

This, however, is not particularly relevant to content moderation on websites.