There are other strong arguments against unlimited PTO that hold more water, at least in the United States.
For one, accumulated PTO is often paid out when an employee leaves the company, and is added to severance should an employee get cut. With unlimited PTO, the company no longer pays anything out when an employee chooses to leave or gets cut.
Second, there is growing evidence that employees take just as few days off on unlimited PTO policies versus traditional policies, if not fewer. Employees experience peer pressure to not be the one to push the boundaries of “unlimited” (which absolutely is not unlimited in any real or legal sense of the word). Also, simply changing the allocation of PTO does not change the culture of acceptance of PTO; that is entirely orthogonal to “unlimited PTO”, and has to be addressed by changes to company culture and education of managers and employees.
It’s important to recognize why companies, as for profit business ventures, want unlimited PTO. First, “unlimited PTO” looks good on benefits package documentation for the company. Second, the company carries zero liability for PTO on its accounting books. Third, the company has smaller payouts when employees leave or are cut. Fourth, while their employees are there, they take no more PTO than they would otherwise.
As an employee, who will almost certainly leave your present company at some point, you must really think critically if this unlimited PTO also benefits you. Evidence isn’t in your favor.