Current system encourages women to become professional mother by having as many kids as possible. The kids which netheir them, nor the state can afford. Often those kids are unwanted, done just for the money.
Everyone has a right to have children, but some people go on to abuse the system by having a dozen of kids at tax payer’s expense.
Yet, my wife and self, on average UK salaries, could hardly afford to have one or two kids.
It doesn’t make any sense to pay for excesses of the others.