I read a book written by a famous rapper, LOGIC (or Bobby Hall), called SUPERMARKET. When I was reading through his book, I realized how informal it was written to such an extent, proper grammar was less emphasized. Less emphasized in being that it was loose. This wasn't the first time where I read a book where the grammar was loose and the writing very informal. Books by Bill Myers, a Christian author, writes in this style. In my personal opinion, it can take a person out of the book when they have to correct the writer's grammar. Now, now, now. I can certainly see this style being useful when it comes to Young Adult fiction, and how most YA novels tend to be in first-person. Writing in first-person can afford you liberties to write as if you're writing a diary. This can be a plus. But my main question is, do traditional publishers care more about author platform than writer integrity? Writer integrity being something that readers of literary fiction often prize. Beautifully written fiction that shows the hard work of the author. Respecting the rules of grammar, etc. I have become convinced that LOGIC's book got published because he was a successful rapper.
Publishers care about money, like any business really. They need to pay their staff and themselves and that means they need to make money.
There are two ways for a book to sell a lot of copies. Either the book itself is good and appeals to their target audience. Or the person writing it is famous enough to generate enough interest that people buy it.
Now an Authors platform is a far better guarantee of sales than the book itself. You know their audience will most likely purchase it and like it, because they already like the author/writer and their associated style. You also get a ton of free marketing from the famous person advertising it. So why wouldn't a publisher favor it?