These hypotheses can look interesting to begin with. By the time you've heard seven more that are equally compelling but mutually exclusive, you're a lot more sceptical. People cherrypick findings, stressing those that align with their pet theory and conveniently ignoring those that either don't add up or actually contradict it. I'm sure they believe in them sincerely, but belief is so unhelpful in science that starting to develop symptoms of it should probably sound a loud hooter with flashing red lights.