> but if the rule you use is "if they look like a crank, ignore everything they say", then you miss special relativity (and later general relativity)

No you don't, you just don't catch it right away, relativity actually holds up under scrutiny. Besides, I reject the premise anyway.

Einstein did serious work on the photoelectric effect first and then gradually worked towards relativity. Outside of the pop history he had very little in common with cranks. This is basically the result you end up seeing when you look into any of these examples used to try and argue against the ability to pattern match cults and cranks, the so-called false negatives never (to my knowledge) actually match the profile. Only the fairy tale built around their success matches it.

So it is with cult-ish behaviour as well, these are specific human failures that self-reinforce and while some of their behaviour occurs in successful people (especially successful and mentally ill or far from neuro-typical people) there is a core of destructive and unique behaviour evident in both that you absolutely should recognize and avoid. Not just the statistical argument that you will gain much more than you lose by avoiding it, it's that it is staggeringly improbably that you will lose anything.