If WCAG does not make content fully accessible, why is it the standard?

One of the reasons why WCAG is commonly referenced as the standard is because it is one of the most robust and well-vetted standards out there. It is heavily vetted by the international community— from folks from the technical side to users with disabilities and stakeholders. Although imperfect, it is an extremely valuable tool in creating a solid foundation and helping create a shared understanding of accessibility.