silos that have a "mute" feature for hiding posts from people so you don't have to see what they post, without having to unfollow them.
Flickr - added in 2007?
Facebook lets a user remove content from their news feed in several ways, all accessible right from a singular post:
- Hide post. This allows the user to permanently hide a specific post.
- Snooze Author for 30 days. This allows the user to temporarily hide posts from a specific author.
- Hide all from Author. This allows the user to permanently hide posts from an author the user isn’t following themselves. The post was put on their timeline by the Facebook Algorithm because a friend interacted with it or shared it.
- Unfollow Author. This allows the user to permanently hide posts from an author the user is following. This isn’t “hiding” or “muting” so much as actively unfollowing a feed the user themself previously choose to follow.
Some form of muting has reportedly been available since 2010(?).
- Mute an account 
- Mute Tweets that contain particular words, phrases, usernames, emojis, or hashtags 
Flaminga was (site went down ~2014-12) an in-development Twitter client that proposes some elegant solutions to spam and abuse on Twitter.
- Shared mute lists. Subscribe to a friend's mute list
- Mute tweets from a muted user's followers
- Mute tweets that mention you along with a muted third party
- Mute brand new users (configurable 1 day to 1 year)
- Mute users who post too many repeated links, or who are muted by others