I see what you're saying, but you have to understand where they are coming from. I happen to agree with many of their grievances too.
A lot of the CBR people have been fans since at the least the Hudlin years or earlier (Priest years, McGregor years for example). This means that they were fans since T'Challa received his first major L against Doom, an L that almost killed him and resulted in him no longer being the BP and ruler. Ever since then, T'Challa--and sometimes his supporting cast and Wakanda--has been taking L's and pyrrhic victories for almost 7 years now. Only time that didn't happen was during the Liss run, and T'Challa was in Hells Kitchen away from Wakanda and his supporting cast, until the near end of the run (the Liss run was at its best once his supporting cast and Wakanda got involved). Stuff like Doomwar, AvX (
) and the Hickman run didn't help matters much either.
Coates comes in with a lot of hype and, unfortunately, we have a story in which T'Challa seems mad unsure of himself, rapes by chieftains and human trafficking ops are happening unopposed under the royal family's nose, and T'Challa is going through mad struggles again with seemingly no light ahead of the tunnel. The CBR guys have seen this for almost 7 years now, so they are rightfully tired of it. I don't blame them at all.
I personally hope that my suspicions of the Coates run end up being wrong and that this story-arc and future story arcs are overall great stories that we can look back on positively. The run so far is well-written and the art is on point. Being that we are only two issues in, I try my best to give it a chance, especially being that some of the runs I've enjoyed in the past, such as the Hudlin and Liss runs, didn't necessarily have great starts but ended strong, imho. Not to mention that the current run is selling very well at the moment, especially for BP. Regardless of my feelings of the premise and the book, that is def a positive in the long run.
That said, I hope things turn around soon storywise. I'm not a fan of reading my favorite hero constantly taking loses and/or pyrrhic victories. At some point he has a have a clear win, especially in his own book. If he can't get a win in his own book, where else can he get it?