Sam Altman acknowledges that stories of this behavior are not "super rare", but that "most" stories don't get told for obvious reasons. Y Combinator states that Demo Day is attended by "most of the world’s top startup investors." This is a large group of people.

Given the size of the investor pool and apparent prevalence of this behavior, the "nearly all the investors we know are completely upstanding and professional" statement is preposterous. There is simply no way for anybody to know all of the investors who are behaving badly, and the "even one inappropriate incident is too many" statement minimizes the regularity with which it is clear this behavior is occurring by subtly suggesting that these are isolated incidents.

You have provided neither the evidence nor the logic that could guide us towards your extraordinary claim that it is "preposterous" that most of the investors YC works with aren't harassing women.

I didn't claim that most investors Y Combinator works with are harassing women. I stated that it is preposterous for Y Combinator to suggest that it knows that "nearly all" investors it's dealing with are "completely upstanding and professional." As I wrote, "There is simply no way for anybody to know all of the investors who are behaving badly." As Sam Altman has acknowledged, most instances of this behavior go unreported, so most of the folks engaged in it are not known to be engaged in it. If you can't follow that logic...

Your suggestion that I somehow claimed most investors working with YC are harassing women is so absurd as to be comical. I don't know what your agenda is, and frankly don't care, but if you're going to try to distort what I wrote, I'm confident you can do a better job.

I don't think he was trying to put words in your mouth like that, but either way... There is some logic, yes.

Is it possible that YC affiliates with higher-caliber VCs that are less prone to this behaviour?

Is it possible that "super rare" occurrences and "mostly unreported" occurrences are both very low numbers, to the point that YC can expect not to have any incidents?

I think the answers to both could be yes, but I don't know if anyone has numbers to support anything. Anecdotal evidence from often anonymous founders indicates that there is a problem, but I honestly don't know how out-of-control it is.

Either way, good on Sam and Jessica for addressing the issue.