I'll just leave this here:
Those quotes IIRC were in the context of people complaining Sins was to much 2D and not enough 3D.
Also, star bases and mines were not part Sins at the time.
A possible reason for why z-axis exploits exist could be that a) it's not easy to figure out. so rarely used it's been shunned by the ICO community to a large degree where a majority don't use it.
In some ways the anti-z-axis goes a bit too far with players rage quiting because they don't understand the game does indeed use the z-axis and ships will indeed move in the z-axis to avoid targets. I've seen this and the typical z-axis exploit rage quits occur, though rarely, over the last couple of years (though I play much less regularly in the last year or so to know if it's happening more, less or about the same).
This whole argument seems very similar to the service & repair application I work on. We were informed by corporate security that it's not technically fraud when our users exploit holes in the system because the system allows them to do it. Interestingly we call it gaming now when they exploit the system to order more devices than business rules would normally allow. We are in the process of identifying and closing those holes in the system to prevent the exploits from occuring.
What our business clients and us (the developers) have found is it's difficult to think like those who will commit fraud or gaming. Even when it is found a decision must be made if the issue can be cost justified to expend project hours and money to be resolved...