THE ROCK and all the aforementioned actioners are straightforward slugfests whose characters fail to develop in any way. Harry Gregson-Williams's chase sequence from THE ROCK features a moment where Nicolas Cage drives past a police car barricade into a hangar, wondering whether or not to go on. At this point, the rhythm stagnates. A mere second later, Cage makes up his mind and blows the hangar's glass gates, at which point the music gains momentum again. 100 musicians would have had a really rotten time trying to catch the ritardando amidst five hundred other hitpoints and get going again that fast.
Flexibility is therefore another plus.
Electronics also allow to deepen the dynamic range to subwoofer shakes and beyond. In the era of the digital soundtrack, electronics have bigger potential than an orchestra. A battery of synths has the merit of sounding extremely massive. Just check out THE ROCK 's theme, presented over the main titles, and you'll know what I mean. Dynamics are another plus.