"Extraordinary claims require extraordinary evidence" is a very misguided, logically fallacious principle. Extraordinary claims require the same, reasonable, evidence that any other claim requires. The idea that something rare or hardly believable to an individual's mind means that individual deserves evidence of a truth beyond what is normally required to support a fact, is silly.
"The earth is flat."
That doesn't require extraordinary evidence. It just requires the usual, reasonable, amount of evidence. There just happens to not be any.
"The Pope flipped the bird and cursed a guy out on live TV."
That'd certainly be rare, and I'd personally find it very hard to believe. But I'm not due any evidence that is "extraordinary," above and beyond some other claim I'm more inclined to believe. Any amount of normal, reasonable evidence ought to convince me.
But, people keep quoting that tired line, and I suspect will keep believing it.
People are crap at philosophy.
The Epstein thing....like anything else, there is an agreed-upon set of facts about his life, and differing theories seek to best explain those facts. And which theory one thinks fits the best can and does vary, usually by how much weight a person assigns to different pieces of the puzzle, and then their view on how likely/unlikely a given theory is for that piece of said puzzle. We'd all like to think life operates statistically on the frequentist paradigm, but in reality we're all doing Bayesian computations subconsciously, all the time. It's not wrong because it's the best we have, it's just going to inevitably lead to differing opinions. The best we can do is be honest in our Bayesian analysis.
I don't have a strong opinion one way or the other about Epstein, partially because I'm aware I haven't followed everything closely enough to know all the pieces of the puzzle that are out there, and partially because what I have followed, I'm personally at a coin-flip vantage point. He killed himself, he didn't kill himself.....he was some kind of intelligence operative, he wasn't.....all I can honestly say is that I've heard decent cases for how the facts of his life plausibly fit either theory, and also criticisms of each side's case which also seem plausible. I'm not claiming the truth is unknowable or criticizing anybody who believes one way or the other. I'm just saying I don't know what to make of it.