I'd be very willing to bet that the same qualities that drive someone to use a crude username may cause that person to be less desirable in several aspects of professional life.
Their username suggests that they're related to the porn business (dong == penis). Stripe (and any credit card company) has rules about the types of businesses they will support/allow. Porn "Adult" sites are on the prohibited list. https://stripe.com/ca/prohibited-businesses
Or maybe the user just enjoys penises, or wants more dong for himself at a personal level. Not everyone uses HN as an extension of their business/professional interests.
perhaps - but the parent was questioning that the username did not provide a hint about the reason. I think it's fair to say that's a reasonable hint. It may or may not be the actual reason he was denied of course.
