Hoshen Mishpat in our time

Here, reason dictates that the laws of the Torah govern and determine the order of life in the most correct way.
And I started studying Choshen Mishpat in the kollel and I can’t understand what’s going on here.
For example, it says that only the Bible is needed, and if there is none, then we only discuss what is common, but that leaves the world empty of many other things.
Like a person who harms another person, according to the Torah, he is not supposed to pay for his actions.
Until the geniuses had to take a crooked path to save the terrible situation it caused
And this is the Torah as it is said, “Because of your wisdom and understanding, will not any Gentile who hears such things value the Torah, to put it mildly?”
Another thing that is very incomprehensible is a concept that I have come to understand – that in recent centuries, the judges no longer decide the case but only leave it in the hands of the defendant – and again I ask, is this what a normal legal system is supposed to look like???