SV CEOs go on interview shows and talk about getting advice from each other. We're not only going by results here, but by self testimony. They also demonstrate the same idiosyncratic biases -- which very often involve the mislabeling of beliefs they don't like. They behave in concert, often taking similar actions on the same target, all on the same day.
I agree with you that they probably aren't explicitly conspiring or coordinating with each other, any more than millennials explicitly conspired or coordinated with each other to all start wearing skinny jeans. But, to stdcredzero's point, there doesn't necessarily have to be an explicit conspiracy for there to be a legitimate concern here.
One prominent reporter calling a couple payment processors and asking the same question - "I'm doing a series on why you help <bad person> fund their operations" does the trick just as easily as a big (extremely risky) conspiracy.
