OK, I may have overstated the case. And of course there will be varying opinions of what constitutes a "pure shooter." But at this point we are in a chicken and egg discussion - do we have lousy shooters, or is the offense getting them lousy shots. It may very well be both.
However, I have not seen enough of these guys to vouch that they are not good shooters. And we keep hearing from Smart how well they shoot in practice.
On the other hand, I have seen this offense for that last 3+ years and it is a stagnant, awful mess. We don't consistently get guys free looks, our guys don't consistently move off the ball to get themselves into a prepared shooting position, and we don't consistently deliver crisp passes to enable a quick, accurate shot.
So in this chicken/egg scenario, I'm of the opinion that the prime factor (and the most easily fixable) is our offensive system. I may very well be wrong, but that's what it looks like to me.