Basically, the proposal will allow websites to check if there is a real user on the other end, instead of a robot. It uses a DRM style token system to do it. The problem is that this would restrict the web to just those browsers that have an implementation of the DRM. The only implementations of the DRM available are from Google, Apple, and Microsoft. Anyone not on a browser approved by the big 3 would no longer be able to use the web.