I was following their Dota project from the beginning, and I think what they did made sense. Their goal there was to demonstrate real time decision making and teamwork in a complex environment without perfect information. OpenAI Five did a splendid job of doing that.

I would view it as the equivalent of making self-driving cars that are constrained to a single city. Sure, it doesn't have the full capability that a human would have. But who cares.

Not really, no. There will usually be allegations of malfeasance floating around a person for a while before any of them are brought to the wider public. To a complete outsider, it looks like these things come out of nowhere, but to someone who's relatively close to the person it seems like it was building up for years. I've also noticed in cases of false accusations that there will often be a number of other accusations made shortly after, all of which look relatively weak or unimportant; eg someone accused of sexual harassment will separately be accused of making a sexual advancement then backing off when turned down. By evaluating the sorts of other allegations about a person when some accusation is made against them, we can attempt to guess the legitimacy of those allegations collectively.

Actually no, it often is not how it works. For example, Harvey Weinstein's behavior has been "open secret" in certain circles way before the scandal exploded. Epstein has been known to be super shady way before he found his end in prison. Anthony "Carlos Danger" Weiner has been known for his exploits well before he finally was prosecuted. There are, of course, opposite cases, where certain sociopaths meticulously cultivate their benign image and hide their true colors. But often, the true colors are known if not widely, then at least by many people surrounding them. For a reasonably public person, it would be quite hard to lead a double life for a long time without anybody at all knowing.