https://www.revsys.com/tidbits/greet_pause-a-new-anti-spam-f...
I get several thousand SPAM attempts per day: I estimate that this one technique kills a large fraction of them. And look how old the feature is...
I don't consider GreetPause to be a form of shadow moderation because the sender knows the commands were rejected. The issue with shadow moderation on platforms is that the system shows you one thing while showing others something else.
Legally speaking, I have no problem with shadow moderation. I only argue it's morally wrong and bad for discourse. It discourages trust and encourages the growth of echo chambers and black-and-white thinking.
No such spam folder is provided to the public on social media.
Only if the recipient sent a false response.
If the response were misrepresented then I would object to the technique. But it doesn't sound like that's what happens.