They produce different textures and tastes.

If you want to reproduce the texture a recipe had, then those are what you need. If not, then don't.

But it's not like flour or corn starch or sugar or corn syrup or baking powder are fundamentally different from most of the ingredients listed. It's all refined and modified and engineered. Baking is chemistry. And if you want to be able to make a wide range of textures and tastes, you need to be able to tinker with all those things.

Obviously you don't have to, most people stick to the most commonly available ingredients. But then you're just more restricted in the possibilities of what you can make. Maybe that's fine. All depends on what you want to make.