first off Galileo's observations weren't too surprising, and remember this is after Copernicus, so he wasn't too outside the box, indeed, Vatican astronomers were reaching the same conclusions as him at nearly the same time, its just that Galileo was an asshole and decided to attack the Pope in his famously published work, calling him an illiterate simpleton. You know how that ended.

But even more importantly, Galileo had EVIDENCE to back up his ideas, and that evidence, observations, and experiments could be repeated by anyone who was interested enough to do them. Not so with Sheldrake, what experiments are done he dismisses all possible explanations but his own pet theories, or he looks within the noise of statistical analysis and thinks its conclusive in favour of his theories. He is the epitome of a man who is dogmatic in his beliefs, he is the fundamentalist.