Isn’t Ijma And Tawatur Just Opinions?
Then to call salah fard in the way it is today would be haraam because to call something fardh is only Allah’s domain
That’s an assumption that the difference in rituals didn’t occur before the splitting of certain groups. Eg people started doing rafa yadein and differing or sadl vs qabd before the different groups that do them split apart
Ok that point about Christians is fine. But if the prophet صلى الله عليه وسلم wanted to establish one way he could’ve. That doesn’t mean that over time certain people could’ve made their own way in certain locations. How do we know whether sadl isn’t a bidah? Just because we don’t have evidence of it starting at a certain time doesn’t mean it didn’t start at a certain time. We wouldn’t know.