It should be blamed on Black internet users.
It is far more likely that an Urban Black will use that term as a descriptor than an average white person.
The truth of this is also pointed out by the unique spelling - with an “a” at the end rather than the letter “r”.
People using that term as they do in their speech, the “urban phonics” of the epithet is decided preponderant with the spelling “n***a” or “n***ah.”
I agree. I’ve heard racist terms, but the N word is a rather antiquated one. I’ve never heard a white racist use it with an a at the end.