I don’t particularly care if Black folks say nigga. I use the word more than I’d like to (not as much as Aaron McGruder apparently), but the meme that it’s basically a term of endearment among Black people is flawed at best. If I say “fuck you nigga”, I’m not exactly you showing you love. The word gets used in this manner often.
I generally don’t care if you use it, but let’s drop the pretense that’s it’s always or even mostly used when showing love to another brown person.