The thing is, I'm not even going to say he's a bad writer. The potential for dope shyt is clearly there, he's just the WRONG writer for Black Panther. Coates never liked the character as a kid and as he read up on the character for the job he still didn't like the character. Whenever he talks about Black Panther and the previous runs all he talks about is the shyt he didn't like or that didn't make sense to him. Dude has been on some "fukk T'Challa" shyt since day one and it comes through in his writing.
Even when he talks about his favorite characters to write in THIS series he never mentions T'Challa.