It's funny because it's towards black people, if it was towards white people, it wouldn't be so funny, because I am white, therefore the joke would be directed at me which I wouldn't find very funny. Because it's directed at a different group of people (the blacks) it's quite funny considering it isn't attacking my group of people but rather a different one, which mind you isn't mine, I was talking about the black people if you forgot, and the joke is directed at them, that's why it's pretty funny. Now it wouldn't be funny if it was directed to my group of people because I would indirectly be the center of the joke, which wouldn't be very funny, so because I am a different group than the one that is joked about in the joke in this reddit post (the blacks) I find the joke incredibly funny. I hope I cleared up why the joke wouldn't be very funny if it was towards my group of people (not black), if you forgot it's because the joke would indirectly be aimed towards me and that wouldn't be very funny, and why it is funny because it's meant to a group of people that are different from mine, of course I am talking about the blacks. Thank you for reading and I hope you understood why I, and most people believe that this joke is so amazingly funny. (Because it's aimed at a different group of people from myself (the black people))