In my experience, to work on one or a few bikes, as opposed to some sort of mass assembly process, a powered screwdriver is not necessary. Most bolts only need to be turned 5 or maybe 10 times at most, from initial assembly to tightened down. Maybe if one has mobility issues or joint pain then it could be helpful, but a foldable allen key set is likely almost as fast, and more reliable, than a powered tool in many situations.