No. In a worst case scenario of all negative results getting something and all positives being blank removing setback is far better. you are minimizing your risks. You are still referring to averages. And why are you counting 2 boost to 2 setback? almost all setback reduction abilities take away two, but almost all boost add one, precisely for the reason you stated of boost dice being slightly stronger.
2 ranks of Precise Aim take away 2 Setbacks, a double aim adds 2 Boost, I don't really understand your point.
You're also judging this by a single snapshot of a single roll which is a completely incorrect way to determine the value of a talent that influences a dice roll. If you aren't considering averages over time you aren't examining it accurately.
Edited by 2P51