For what the Racing legends are trying to achieve, there is no single computer with enough processing power in sight to deal with all those (magnificent features) it is trying to simulate. It is like what Drivers' Republic is trying to do with everything modelled in physics and calculated real-time. Not sure about how many people are coding it, the system to handle and adapt to all various conditions must be very advanced.
As said earlier, there are people telling that it is very alive, which is probably true. But what are the aims of RL today, is it still a consumer product or is it more of real life racing team software with real life racing costs and services...