Are Squats worth 3kg of quad mass??

Considering muscle weighs more than fat?. Or is that just a myth?.

“…One liter of muscle would weight 1.06 kg (1060 grams) and one liter of
fat would weight 0.9 kg (900 grams). In other words, muscle is about 18% denser
than fat. …”

Would it better for a sprinter to develop just the CNS, relative strength & cut hypertrophy as much as possible?.

Why would you continuously want to keep adding mass?.