Jokes rarely are. It's a joke and as such it shouldn't be taken seriously.
> Millions of Nigerians work honest jobs to feed and educate their children.
Nobody is implying otherwise.
It's hard to appreciate the other party's POV unless you've lived through the stigma of prejudice that's perpetuated by jokes such as yours.
That said, it's okay. Your comment shows you didn't mean any malice so as an implicit apology, it is accepted.
You've had personal experience with stigma for being Nigerian because people you talk to think you’re a scammer? Willing to share/elaborate?
Jokes rarely are. It's a joke and as such it shouldn't be taken seriously.
> Millions of Nigerians work honest jobs to feed and educate their children.
Nobody is implying otherwise.