There was also the whole Godwin thing (that basically said that any online argument would, over time, have a higher chance of someone accusing the other party of or making a comparison to nazisim), which eventually evolved to "if you mention hitler or nazis in an online debate, you automatically lose", which was pretty stupid because sometimes it is relevant (obvious today).

Though today I wonder if that was pushed in bad faith by people who wanted to avoid nazi comparisons because they were apt, so pushed that pseudologic bs that Godwin's original statement got perverted into. And then it was picked up by the multitude of people who just want an "I win" button for arguments.