I'm almost positive they do and I've done it myself?
Edit: lol -9 for this, and I double checked and you absolutely can hide your game activity in privacy settings. This place really is no different from reddit.
If you read the above comments, we're talking about blocking specific games. Your low score is not hivemind, you just missed the context of the thread .
Steam is all or nothing, and if you block everything, some games won't allow you to invite friends or join games, and it's not just a switch to flip to turn back on for multiplayer. You have to go through several menus to change your settings. We've been asking for the ability to block specific games or just turn off participation in the feed for ages.
Also unlike Reddit, your points aren't tracked and mean nothing here ,so there's no point in worrying about downvotes.