The latest harassment campaign occurring over a Steam profile and community posts should be less surprising than it is, TBH. Valve's hands-off approach to moderation, along with creating a forum for every single video game, has led their Community tab to be one of the most toxic hubs on the Internet. Turning off the forum feature in Steam wouldn't fix the toxicity, but it'd sure as hell give it one less space to fester unchallenged.
