You are proposing linkrot on an unimaginable scale. You're talking about breaking the Web, on purpose. It will never happen, and for damn good reasons. This horse left the barn several decades ago.
Your proposal would break it an order of magnitude more, easily.
Also keep in mind that domain names are treated as property in most jurisdictions. You cannot take away someone's foobar.co.uk domain just because you want to retroactively change policies. It's not even possible from a legal standpoint.
