Our immigration system is indeed hopelessly broken. While there's a lot here about O-1 being fairly objective and checklist-based (no idea if that's actually true, just taking some comments here at face value), other visa situations can be arbitrary and opaque. And don't get me started on the ridiculous, arbitrary, capricious green card process.
> There is no obligation for the US, or any country, to turn something as important as determining whether someone is eligible to enter the country
I have the opposite opinion. Borders should be much more open, and people should stop whining so much about immigration. Nearly everyone -- aside from the relatively small number of Native peoples -- in the US is an immigrant, or the descendant of immigrants. We are all here because our ancestors forced their way here, killing and destroying wherever they went.
The idea that we have some natural right to decide who comes and goes is entirely laughable to me. I get that we should have some controls in place for at least logistical and security reasons. But our immigration restrictions go far beyond that. And again, let's not pretend it's some natural right of ours to do. We get to do it because we've had more guns than other people who wanted to be here and "own" the land.
Also remember that this is not the normal or common state of things. The internationally-recognized passport system we take for granted has existed for barely a century[0]. Before that it was a patchwork of various systems (sometimes just the honor system) and much of what we'd call "illegal immigration" today was the status quo. On top of that, the US's restrictive immigration system has existed for an even shorter time; when my great-grandparents immigrated about 115 years ago, all that was required was they enter through an official port of entry and truthfully declare who they were and where they were from. They didn't have to have a visa, or apply for permanent residency. My great-grandfather became a citizen about 15 years later shortly after applying and providing a record of his original arrival in the country.
Meanwhile, today, adults who were brought here by their parents as toddlers ("illegally" -- like a 2 year old has the capacity to do something illegal) can't even get legal residency or citizenship. If that's not hopelessly broken, I don't know what is.
The funny thing is that we're talking about this in the context of someone suggesting that OP "hacked" a broken system to get a visa. But it sounds like the O-1 system is pretty functional and is working as designed. There's a list of criteria, and a lot of explanation as to what is and isn't covered under those criteria. You document, make your case for why you fit the criteria, and apply. USCIS makes a decision (and pretty quickly, at least in this case!), probably based on a checklist, by people who likely don't really understand the nuances of any particular industry or profession or academic discipline to make any sort of value judgment on the application, beyond the checklist and the case being made. That... seems exactly how it should be? A transparent process with well-defined criteria for acceptance? (You may disagree with the criteria, or the list of things that qualify, but that's a different matter.)
[0] (The idea of passports have existed at least for a couple thousand years, of course, but in the earliest days they were more like a hand-written letter asking, "please allow my subject, Bob, to pass safely through your lands, signed, King Larry".)