Bill de Blasio, the much-disliked mayor of New York City, has virtually no chance of winning the Democratic presidential nomination for 2020. And it is a good thing, too, because his grandiose Workers’ Bill of Rights is a sure-fire recipe for economic disaster. His proposal tampers with every key feature of employment law.

Mayor de Blasio believes employment relationships are a zero-sum game, and he wants to strengthen the position of workers against their employers by kneecapping the latter. He insists that employers be required to provide paid family leave, pay higher wages, and to treat all temporary staff as “employees,” so that they too receive statutory protections. Additionally, his proposal mandates that employers may only terminate employees “for cause.” These recommendations, among other changes, would strengthen labor unions. To de Blasio, for workers to win, employers must lose. He wholly misses that by his proposal their fortunes are linked together in a lose-lose embrace.

Several flawed assumptions undergird his Workers’ Bill of Rights. First, he repeats the common claim that the position of ordinary workers has stagnated over the past four decades. But this claim is rife with difficulties. The quality of goods and services has significantly improved over time—computers have replaced typewriters, and smart devices have made rotary phones obsolete. No one alive wants to go back to the 1970s. Wage measures cannot adequately capture quality and lifestyle improvements. Also, wages are a smaller fraction of an employee’s total income due to the rise of fringe benefits.