@ Demi
Well, it really has two reason for exist at all
A. As I.S. mounted weapon, being more complex than working sample is no problem as long as it's reliable (it was developed from bigger 30mm coilgun currently in military service, in universe that is
)
B. Being sturdy and heavy as a metal club of same size, like comparing Kalashnikov to Western assault rifle. (The original coilgun lacked complex, reinforced frame housing and stuff like that, opting for simple and reliable suspension and mounting similar to what most Tank guns have)
@ Eras
Well, it's not like happy go lucky harem nuclear family is realistic either, the worst ending is theoretically possible and while some will complain, it's not a 'true' ending either.