Yup, it does. But that's not the only thing it can do.
In fact, the US Navy's Virginia class submarines are a great example of an operational system that is, in an absolute sense, kinda big and expensive, while still being quite FISTy. And when I say FIST, I'm talking "delivered 8 months ahead of schedule and $54M under budget."
So yeah, the FIST approach can result in a system that is simple and inexpensive in an absolute sense. It can produce a prototype that isn't supported by any sort of logistics tail, isn't well tested, etc. Sure, we can do that. But FIST can also produce fully-operational nuclear submarines. Want to read more? Check out More For Less, from the Navy's Undersea Warfare magazine.