I think the "this is unbelievable" comments are coming from people who have worked in the industry for a long time -- but not at Uber -- who are surprised that this sort of thing not only goes on, but that HR appears to be advocating the behavior through inaction.
At least from my anecdotal experience, I've never seen anything like this among the four companies and 20 years I've been in software development and engineering. Granted, the percentage of women who were in technical, non-management, positions[0] hovered around 20%. In those cases, the skillsets of the women ranged as much as it did the men and all of the folks I worked with treated each other, regardless of gender, respectfully and professionally.
I wouldn't imagine seeking a date with co-worker. What happens when you break up? Do you want to bring that to work with you ever day? At the companies I've worked for, I know of one incident where a person was let go for "having a crap-ton of porn on his work PC" that someone from security noticed when the proxy logs flagged his workstation. This individual was a VP, a "high performer" and was very well like. He was also out on his hide a few hours after his laptop was seized and inspected. This was with no reports from women even hinting that he'd acted inappropriately on the job. And we had nobody inspecting proxy logs looking for this sort of thing -- that guy in security who happened upon his workstation ended up being there because he was investigating a malfunction, but because of corporate agreements we'd all signed, he was obligated to report what he found[2].
I hate to say it, but this is the kind of behavior I'd expect out of teenagers, not adult men. And it's one of those things you usually don't have to tell people not to do. Though I have no experience with this specific kind of behavior, I've noticed that when people fail on morally obvious things, they're often failing on many other things and I would be worried if I were an investor about having my money tied up in a company that had this kind of a reputation -- what other laws does this corporate culture find acceptable to break? I'd be twice as concerned if this were my employer -- not just out of fear of being harassed, but out of fear that a company with these kinds of ethical lapses is often quickest to screw those who work for them (or take them down with them). No way.
[0] Perhaps my experience is unusual, but for 17 years the VP level individuals in my teams have been women, I've reported to a Director level employee who was a woman and I've had a woman for a manager on more than one occasion.
[1] Thus far, I know only of this account, which without additional data is as anecdotal as my comment, here, but based on others piling on, I am inclined to believe that there's a real problem here.
[2] Paraphrased, we were basically required to report everything even if we were not directly involved, but if I saw something this inappropriate, I wouldn't need a signed agreement to persuade me -- I had full confidence in the HR teams at the places I was at and knew it would be handled appropriately.