CORS can fully stop an origin from accessing an http resource, this discussion is about allowing different origin to reuse the browser local state (like cookies

CORS can fully stop an origin from accessing an http resource, this discussion is about allowing different origin to reuse the browser local state (like cookies, http cache, local storage). CORS is a stronger security layer in the browse than cache segregation, some people want to keep the CORS security model but weaken cache segregation.