I feel you. Apparently rule 3 goes out the window when people believe something was created with AI. Like do people not get the implications of how easily serious conversations can be derailed if people can just claim AI and poison the well about whatever was said. It's unprincipled, reactionary behavior. Wrestling with ideas rather than individuals is pragmatism in the context of relative anonymity online, not just about being friendly; we can struggle over an analysis regardless of who or where it came from. If we have to know where it came from in order to do so, internet discussion becomes limited to only discussing information direct from public sources.

That said, people shouldn't take everything they see on the internet at face value, including from public sources. Even liberals would probably agree on that one. But there is also never going to be a magic formula or intuition or vibe check for discerning when you're being deceived. Only careful investigation can consistently and reliably reveal that and it's simply impractical to be thorough with everything posted online, so you have to sort of read in a fixed state of one eyebrow raised without making your head hurt and your tone hostile.