Following News, I made a change to the “no trolling” rule in Politics and World (rule 4 for Politics, 5 for World)
“Similarly, if you see posts along these lines, do not engage. Report them, block them, and live a happier life than they do. We see too many slapfights that boil down to “Mom! He’s bugging me!” and “I’m not touching you!” Going forward, slapfights will result in removed comments and temp bans to cool off.”
Unless they follow the rules and do not engage.
So one piece of well-placed libel that isn’t enough by itself to incur moderation.
Ignoring it lets the libel stand. Ignoring it enough turns the libel into accepted wisdom. Reporting it does nothing because it’s not enough by itself. Engaging with it results in repetition of the libel. Few cycles of that, slapfight ban.
Reporting as misinformation would get libel removed.