Low deflection shafts exist for the beginners who want to spin the rock all over the table before they learn how to properly aim and stroke the ball. Players that cannot reliable make a ball and do not know the real reason why they miss shots, assume it must be deflection. The genius of the plan is that when one shaft doesn't fix their"deflection" problems they will buy a new shaft that will. When they shaft doesn't work? We've all seen apa threes dragging dealer cases into bang balls around a bar box.
Having said that, there are players who are experienced enough to know why they miss. Although it is not deflection that makes them miss, it is their inability to or their desire not to adjust for the deflection. That person may benefit from a low deflection shaft as long as they learn how to use it. This isn't a bad thing it's just a personal preference. Some people will argue until they're blue in the face that it is universally and objectively easier to use a low deflection shaft, but those people are just placating themselves. That is not a bad thing either, if you think something is easier it will become easier.
Proponents and purveyors of low deflection shafts will have you believe that they are point and shoot, meaning hit where you aim, news flash you always hit where you aim! Now where do you aim? Low cb squirt from a shaft does not solve the problem of aiming a rolling cue ball, it only slightly changes the equation. Squirt - swerve + throw = final aiming point. You're not erasing the squirt all together your just making it a different value. All three of these work in unison to get you to the correct contact point.
Finding the balance between these things is what makes a truly great player, not systematically eliminating them so you don't have learn anything. Now if we could just make frictionless surfaces and object balls that don't throw maybe I could start running racks, ooh wait I do that already with a high deflection shaft.
I will offer this one piece of advice, low deflection or high deflection doesn't matter. Pick one and learn how to use it. Everytime you switch shafts out whole cues, you start the learning and feeling process all over again. Now I know your not starting from square one, but there is something to be said for knowing exactly what your preferred piece of equipment will do on an ultimately finite scale. I've been playing the same cue and shaft for nineteen years now,I know to the nanometer where this cue will deliver the ball, even from nine feet away with the utmost extremes of spin. I can easily adjust and run racks with an ld shaft, but when I'm nine feet away and have to twist a ball in, I want the cue that I have done that with a thousand times before.