Ok, so it's poking fun at a certain ethnic group; but it is NOT promoting racist attitudes against anyone, in my view. If this flash had a member or members of an ethnic group denigrating or gratuitously blasting away with Uzis other members of another ethnic group, then it might be objectionable.
As to the stereotypes...yes,one could say there's a few. But I think there is no ill intent there. I also think we should be big enough to laugh at ourselves and our idiosincracies once in a while.
I myself loved the Taco Bell Chihuahua (which represents my ethnic group), but I utterly despise Speedy-Gonzalez. Yet, many find that cartoon charachter funny. And even though I loathe that rat, I can't categorically say that it was conceived with malice. And speaking of ethnic humor, who did not get a good laugh at that Bandido from the movie who said: "Badges? We don't need no stinking badges!"?. I myself did. Was that racist?
Maybe I'm wrong but perhaps we should take ourselves a little less seriously, especially when it comes to humor . I thought this flash was pretty damn funny.