I actually think @tinus_hn, who cited the rules in your link, is right: the rule should still apply because it adds nothing to the discussion to debate the bothood of a user even if they claim so themself.

I think the guidelines are to encourage civility and healthy discussion. That is, to not dismiss an argument by calling the person a bot. But if the person claims to be a bot, I don't see how it can be a community violation to call a bot a bot.

True, I don't think it made sense to invoke the guideline in that context since the guideline surely exists so that you aren't dismissing a comment based on who you think wrote it.