@Kecessa speaks unclearly when saying “public space”—the term they are thinking of is usually “public forum.” source
The rules around what constitutes a true public forum and what the public forum doctrine even means are fuzzy, but in all cases the term refers to a space owned or created by the government.
Thus, a shopping mall, parking lot, or internet forum, being owned by a private company, is not a public forum and can’t really be defended on the basis of the public forum doctrine.
Steam is 'an unsafe place for teens and young adults': US senator warns Gabe Newell of 'more intense scrutiny' from the government if Valve doesn't take action against extremist content (www.pcgamer.com) angielski