The situation isn't as simple as that. A lot of the material one has to learn in order to get certified is actually fairly important. Teaching is not easy and requires some finesse. It helps a new teacher a great deal to learn how to deal with pupils of different backgrounds, learning rates, personalities, and so on. It is not intuitively obvious how to utilize tests to determine both student learning issues and curriculum faults. Teachers also have to identify signs of abused children, and how to deflect false claims of abuse.
I was stunned when exposed to the full spectrum of the teaching experience.
There is a lot of slop in the teacher certification requirements; but, it really can't be discarded out of hand.