A planet's extractors are as powerful as the planet's allegience. Central worlds operate at nearly full efficiency, while border worlds can start off as bad as 25% the rate. Neutral extractors in the game produce at 100% efficiency.
So, here's the thing. When you scuttle a planet, you no longer have allegience in the area. The extractors in the system then jump from the planet's allegience, to 100% efficiency. This basically means you nuke your planet, and get full powered extractors in return.
This is potentially useful for useless border worlds like asteroids and dead asteroids. They give terrible income naturally, and there isn't much to build at one. So instead, put a base there, build some extractors, then abandon the asteroid to maximize their output. It doesn't work as well on better planets, as you have more to lose from scuttling the planet.
So, is this a sort of bug? Or is it a potential strategy to maximize your income?