Well.....
The Mulsanne straight allows you to open the throttle and enjoy the noise and sense of speed.
Yes it is easy to drive round but it is hard to drive fast. Countless people misjudge their braking point into Mulsanne corner. The Indianapolis section is difficult to get right- you have to carry as much speed as you can through the first part without losing the line into the tighter corner, which as it happens is very easy to run wide on. Again take the 2005 version, the Dunlop chicane is a :censored:to get right, due to having to shave off most of your speed before the corner in order to navigate the right turn into the chicane.
Also, because the track is very thin in parts, if you do make a mistake you lose a lot of time due to being off-line or in the sand.
/rant.