As usual it comes down to training. While it may in theory be more accurate, it's still not useful in the long run. A Lt. Col. Lee of the British 44th Infantry Regiment argued in favor of the longbow in 1792, he said that the accuracy if a longbow was no worse, it has a rate of fire four to six times greater, created no smoke, and a "'hail' of arrows shattered enemy morale than a volley of musket". However it was judged ineffective because it could be ruined by a strong wind, archers needed more spacing, and the main reason, "a conscript could be trained to use a musket in a matter of hours, whereas a proficient longbow man would need years if training and development of physique." It wouldn't have been practical in respects to combat and logistics for lowbrow to have been used even in 1792.

This comes from a new source of mine Weapons & Equipment of the Napoleonic Wars by Philip J. Haythornthwaite.

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