Exactly. Creating a new television show, even one building on an established franchise, requires adhering to a production deadline.
The above complaints about the TOS Bible being too shallow seem to presume modern tele shows do not operate under the same constraints. That's simply not reasonable to believe. It's all fiction and today's TV production still makes it up as it goes along. Such detailed writers Bibles would stifle creativity and definitely would not be available on time to produce a series. I'll go out on a pretty sturdy limb and postulate that 785ish page word doc with images has been compiled over years.
Plus, Roddenberry created TOS out of whole cloth, even if he drew inspiration from other sources. He wasn't building on an existing movie, book, or TV franchise.