So for starters. This is not a credible source. We are getting excited/upset about rumors still people. Mods, can we do a better job or these "confirmed" and "official" threads when they are not actually confirmed or official.
That aside, I will say this CAN work in the greater story. Ok yes. Detta's character is certainly firmly placed in a racism inspired attitude. But that's a small detail...let me pose a new idea here.....
SPOILERS BELOW!!!!!! Beware!!!
Ok so Roland gets the horn at the end of the cycle we witness. That means something has changed. We are all rabid fans of this story. We all want this adaptation to give us a new take on the story that is not actually new. What better way than to start our new Roland off with the horn right? This has been discussed time and time again on this thread. But what if we aren't looking far enough.
What if our Roland actually gets to the tower. Finally. After he gets the horn and whatever else he realizes he regrets, he finally makes it. Maybe it's another 1000 cycles. What happens when Roland FINALLY makes it? Does he die? Does the world end? Or does someone else take his place?
It's my opinion that the desire to get to the tower is something that needs to happen for the world to exist. SOMEONE needs to keep this going. Maybe what we get with Idris is another Roland. Another story. Another set of circumstances. Another decendant of Eld. It can work just fine.
All that aside, more than likely they would tone down Detta anyway in hopes to appease a wider audience. Is it the right choice? Maybe, maybe not...but it's likely.
All that said. We do NOT know what is in store for us with this adaptation. And to be completely honest, most of us with be dissatisfied with a 100% adaptation. It would never live up to our expectations. I think Akiva knows this.
Best case scenario is we get a story that is a natural evolution of the story we already know. We KNOW we aren't reading Roland's first or second or third trip to the tower. The tower is really based on the idea of infinity. So anyone who thinks they can't spin this casting to work on their favor is not thinking like this story taught us to think.