The reason for this is the following：
First, generally speaking, ip that can be adapted is a certain number of fans. Why can attract these fans to read it shows that this story is full of some wonderful things and has its bright spots, otherwise no one wants to read it. Since it is attractive, why should it be unreasonable to pay more attention to the plot? It's just gilding the lily. It's not worth the candle.
Second, respecting history and the original does not mean that it cannot be adapted, but that it should be adapted appropriately on the basis of conforming to the original, and the cart before the horse cannot be put. A good TV play/movie brings truth to the audience, especially in history. Many people learn about history by watching historical TV dramas. If we pay attention to the plot and change it at will, it will give people a wrong understanding of history, such as Li Bai in the glory of the king before. Many people understand him as an assassin who finally regarded Li Bai in history as an assassin, just like a CCTV sketch "Jing Ke Stabbed Qin", which is in a mess.
Third, although the plot is a point that everyone is very concerned about, it is also some ways to improve the ratings. However, there are many scripts adapted at high speed at this stage, and no major changes are needed. Too many dog blood plots will also cause people's rebellious mentality, and everyone will feel very tired and don't want to watch it. There are also many original fans who will be dissatisfied with this and reduce the goodwill of passers-by.