The HN title is "Vanced: YouTube adblocker for Android". The app being an adblocker is the one thing the submitter thought was worth highlighting. It is also the first feature the app's webpage mentions. The webpage even has paid ads for other adblockers before going into any of the advanced features.

Given the above, it seems pretty darn obvious why the GP thinks that the real selling point of the app is to block ads. If this had been submitted as "Vanced: YouTube app with an AMOLED black theme", do you think it would be at the top of the frontpage?