Technically free speech only applies to the government censoring people. Privately-owned venues like online forums are fair game for censorship as deemed necessary by the owners.
Still, I do agree that it's not really fair to shut down all discussions about the future of the franchise based on the company's current situation. They probably don't have the PR resources to handle this, so they just shut the discussions down before things get out of hand. There isn't really much transparency here in the first place.