Because the underlying assumption is every car driver is entirely rational, at full capacity at all times with the decision making capabilities of a fighter jet pilot and every time you try to change this they all band together to defend this status quo, even if it means they'll get T-Boned by idiots like posted in the OP.

rather than this person is a bad person and needs to be punished.

She needs to lose her drivers license is the thing. There's societal problems abound, on aggregate, with behaviour like this and it's still very much an individual being a fucking moron. I don't think think this is worthy of jail time or even a fine necessarily, but a person who shows this open disregard for very clear, basic rules of road safety should not be allowed to operate a car.