Keep in mind - homebrew is not self-publishing. Publishing still makes Sony money since they are being licensed to run on the hardware. The indie devs were sent dev-kits like any other big name shop to do their work on (this is explicitly stated when Octodad was mentioned). Homebrew is allowing anyone to write applications on the platform, and understandably (though this is not what I would like to see) they are locking that down still because of the shadow community. If they make it too easy to pirate games, then anyone will do it - not just those able to root the hardware (no matter how easy it may be).

My guess is that the dev-kits are just being made easier to obtain - either via price point or whatever other restrictions are in place.