Twitter calls it "visibility filtering" [1] Facebook gives mods a "Hide comment" button [2] TikTok calls it "visible to self" [3] [4] Truth Social does it [5] [6] [7] Reddit shows all removed comments to authors as if they're publicly visible [8] Open source tools are built to do it [9] [10] Textbooks advocate "disguise a gag or ban" [11] I call it Shadow Moderation [12]. The system intentionally does not show users…
Its newsworthy because Twitter has been publicly denying that shadowbanning has been in place, and they've denied that preferential treatment based on preferences of internal teams has been in place. Both of those are now being shown to be false statements. Glossing over that fact is a great disservice to the conversation.
The use of this stuff is probably in the companies' terms of use, patents etc. The public is still largely unaware that it happens, as evidenced with Twitter.