Free speech and expression are legal precepts. Nobody rational believes "free speech and expression" are synonymous with "I can say whatever I want and suffer no consequences for it," and invariably, these issues always arise because people are mad that they're suffering consequences. I don't know if this is a new idea to you or whatever, but a company's goal is to keep as many customers happy and paying as possible--or at least content enough to keep paying.
I would wager they've noticed how many people are turning off public chats entirely and that this number has steadily increased as the "free speech" crowd has continued to push the limit on what's 'acceptable' chat. Things like this don't happen in a vacuum, they happen because someone pressed the oh-shit button because a simmering problem boiled over in that way so many other things do, where they're not problems until they suddenly are in a big way. So Blizzard's choice is simple and a no-brainer on their end: alienate the relative handful of people on each server spamming slurs and running everyone else out of public chat channels, or allow the public channels to continue their quickening death spiral which in turn exacerbates their struggle to get people into premade endgame content and social groups?
You'd have me fooled considering how many people are treating this like a personal affront to their rights rather than the logical end result of their actions forcing Blizzard's hand, albeit a decade late as per usual when they actually try to clean up their community's laughable reputation.No one here believes their first amendment right is being violated.