What possible benefit could there be to anyone in "golly gee, who could possibly know?" vs. "It's because you're selling cannabis to Iran, stupid"?
My guess is that it's because most people aren't selling cannabis to Iran, and the Real Problem is the liability they [Stripe, et al] would be exposed to if they admitted their billion-dollar system (and/or call center employees) can't distinguish between Cuba and a cubano.
If this company sells T-shirts or something, then Stripe may have acted improperly. If they sell cannabis, then Stripe would have acted as the law requires, as everyone in that industry knows perfectly well. So it's pretty relevant information, and HN readers deserve to have the information they need to make informed decisions. There are plenty of other places online for uninformed outrage bait.
There aren't though. People come to HN to complain about getting fucked over by YC companies because it's basically the only place people will get a response. I'm not saying all, or even most, complaints are valid. But your immediately siding with the YC company just shows your bias, which is expected since you're literally invested in the company.
Regardless of whether or not Stripe is legally in the right, their customer support is absolutely abysmal. And the problem is that this is clearly a trend with YC companies and the fact that people have to vent about it on HN so frequently, and with such fanfare, says a lot.