Why does Mountain Eagle's Police Dog Controller, despite being very high-end, is called a "Police Dog Controller" and not an "Animal Controller"...
Because the Sergeant needs battle partners who absolutely obey commands. Wild animals full of untamed nature do not qualify for this.
Because you can't completely control their behavior, the instincts encoded in their genes might make them uncontrollable at critical moments.
Of course, having strong animal partners is not entirely impossible, but it requires breeding, selection, improvement, training generation after generation...
Currently, those canine breeds that seem useless and are indeed useless are the result of this practice.
Of course, those very strong breeds, like pit bulls, are also the products of this practice.
In the future, it is estimated that people could edit genes directly to create a certain number of animals for selection and then further train and improve them.