A place to discuss the characteristics of the cars in Formula One, both current as well as historical. Laptimes, driver worshipping and team chatter do not belong here.
That feature is almost certainly there for vibration control. Similar to how different guitar string gauges alter their natural frequency and the tones they produce, increasing the section thickness changes the arm's stiffness and mass, shifting its natural frequency and damping characteristics. That helps move resonance away from the critical operating range and reduces vibration transmission. I'd presume they redesigned that arm specifically for Hungry.
