Just because some people refused to follow their texts, doesn't change the facts that it is prohibited in them. Jews still refuse to lend each other money with interest.
Again, just because those Christians and Jews refused to follow their texts, doesn't mean that it isn't prohibited. The Quran documents and confirms this fact: https://quran.com/4/160-162
We spoke to them and they admit it. Furthermore, we're not asserting "religious dogma" by simply reading their books and calling them out on not following them.