The game evolved quite a lot along the years, but what evolved exponentially ware the possibilities of doing excessive damage. There are so many possibilities to do extreme amounts of damage that defenses are futile against them. The only way to survive a good damage-based player for a few seconds is to have pseudo-immunities (like teleport from rep, fake death or similar things).
Ship damage resistance is limited to 75%, which makes sure that most of the players will get 1-shotted by any good damage-based configurations like communities such as DPS league use.
Practically, as equivalent, the average fully equipped MK15-gold ship can be destroyed in 1 to 2 seconds by the DPS-specialized players.
Modifications should be done so tanking could actually work and defensive team work count.
The 75% limit should be increased to something like 95%. That way, tanks could actually have value in PvP and would take some effort to be taken down.
There's also another logic: by using defensive consoles, you can get around 63-65% default defense, which makes most defense powers that boost resistance kind-of useless since the difference would be at most 10%.
By not using defensive consoles at all, you can get to the same amount by using various powers, but this only for a very limited time/in case of emergency. So it is not much to use both types of defense. The difference is too small.
The equivalent in damage would be something like to be useless to have either energy or kinetic weapons.