There have been significant changes to the race over the years. The current version is the "easiest".
Originally, the race was 11 miles longer and ended at the Summit of Mt Whitney. This ended with the actual enforcement of the wilderness permit system.
Also, the original race started at sunrise in Badwater, so the running in Death Valley would be experienced under the sun in the hottest part of the day. The current three wave start just after sundown was possibly initiated to diminish the impact of vehicle traffic on the road.
Several times I have enjoyed being at the finish when the winner arrived. It was very exciting. One time I saw the winner of this grueling 135 mile race attempt to eat a Pancake. (The store stayed open very late.) But race winner was defeated by the Pancake!
Jim