You can ask sanguinity, when I first watched S1 I spammed her with all my complaints about how irresponsible Sarah is and how bad she is at obvious tactical stuff. And yes, especially as the whole narrative of the show tilts toward John being the (potential?) savior because he's the one who understands how terminators work and understands how to reprogram them, it becomes more and more glaringly dangerous that Sarah is afraid of computers.