It's all the driver.
You just have to know how to drive a rear engined car to understand the advantage over some other types of car formats.
The rear weight over the drive wheels is a powerful advantage and disadvantage. The advantage is that the rear end weight offers excellent rear traction. The bad is that if the rearend breaks loose in a turn then it is harder to "catch".
Race drivers can use the rear weight to "turn" the racecars via the throttle (kind of like drifting or rally racing - just not as extreme) and that helps keep speed as it is not shaved off by the front tires. IMHO the front drivers offer the worst setup to be fast on the track (granted some are still very fast) as the front tires are meant to pull, turn, and stop all the time and share no real work load with the rears (okay maybe 10%).
Power slide a RWD car and you will understand!
Yah BMWs and Camaros are fine, but are not a 911 in the turns. Or a hot VW!