I understand your point, but I think the context is more of "They can't even handle a fizzbuzz level problem" and not come up with something quite naive (i.e. s

I understand your point, but I think the context is more of "They can't even handle a fizzbuzz level problem" and not come up with something quite naive (i.e. something like naive RegEx matching), rather than "they can't implement a professional IPv4 validator that takes into account all the intricate special cases with subnets and reserved address blocks."