Well there's the thing. The whole drama about the drag change was done before the update actually hit live and even now people who never even got hit by said weapons are still thinking they are horrible. They are not. If someone can keep the other ship permanently under the drag effect, he could have finished the fight quicker with some other mod like screening. What the current boost disabling drags do is they disable the boost for a little while enough to mess the enemy boost timing in PvP which forces the enemy to boost at an unoptimal moment which leads to more dynamic positioning during the fight (also means the pilot firing the drag has to think when to apply the effect). It's also good for crowd control when focusing an enemy. We have had interesting wing fights with friends for about a week with drags (seekers, pack hounds, frags) and not once was anyone able to permanently disable the boost of an enemy ship even though it's possible in theory. If someone can do that, it already means he has won the fight thanks to superior piloting skills.
... and as far as trade ships needing the boost speed to escape, that's not really true. FDL, Mamba, Krait for example can easily dance around boosting trade ship so if ganking traders is the goal, screening is much better choice. The main point about the importance of the current drag in PvP is to deny the opponent the turn rate of the boost turn and not really the top speed (you can carry on momentum with fa-off, drag doesn't slow you down).
Well, you're too late with this and FDev was too early with the revert promise