Wouldn't hackers already have that incentive? It seems like virtually all sites worth targeting would already be secured by TLS certificates, so the remaining sites wouldn't provide much value to hackers.
So yeah.. enforcing https may be the same as trying to patch a hole when the bag is wide open..
It will simply become even less feasible for sombody to host a site without the blessing of the big cert guys...
Federalization of the internet is where we are going, but I susppose that's just the faith of all media channels..