The engine failuires is to give the pilots a good reason to easy their engines and fly properly.
However this will make more sense when difference in reliability will modeled for diferent aircraft. I think reliability is a important thing since it was a worry in aircraft design not only perfomance. Some aircraft advantage or disadvantage was exactly its reliability and no considering reliablity we are negating its advantages and disadvantages.
And part of the reliability is due to the properly management of their aircraft by the pilots. The reliability is a good feature for harcore pilots who wants more immersion at least until where the technology allows. Some things are impossible to be modelled but if it it can be and its safe for the player (that example of electric chair was silly, discuss with real arguments, not fallacy), why not?
No one wants to change your way to fly. If you do not like reliability disable it.
