The purpose the long-distance shooting is originally deferent between Kyudo and Western archery. In archery, the purpose is to hit the center of the target in the contest, and in Kyudo the purpose is diversion to shoot in front of enemy in a battlefield (Sashiya-Mae) or to send a letter attached to a bow when surrounded by enemy in a battlefield (Toya-Mae). In addition, the origin of Kyudo contest "Dosha" was held in Edo period in 17th century, at Sanju- Sangendo: archers competed the number of shots which is reached to the other side of corridor at the distance 120 m of the corridor of Sanju-Sangendo. The purpose of long-distance shooting in Kyudo is to shoot arrows straightly as far as archers can.
Because the effects from gravity and air resistance, adjusting shooting angle is the important in shooting. In western archery, sight is attached to a bow to increase accuracy: the less variation between shots, the better accuracy. In Kyudo, especially in Dosha, since archers could not hit the ceiling of the corridor, archers had to shoot as straightly as they can: the arrow should not draw a parabola, as I explained in "Junji Miyata won the 3 consecutive championships of Enteki (60m distance) contest at Meiji Jingu".
With a lot of try and errors, Kyudo archers and bow makers at that time found that with the shorter bow as 208 cm -212cm with heavy draw weight (estimated 30kg -50kg /85cm, or stronger), archers could shoot arrow straight at the 120m distance with the 5m height limit.
Therefore, the bow equipment of western archery in long distance shooting has the advantage of sight which adjust shooting angles.
The bow and shooting method of Kyudo have advantage of shooting long distance straightly, meanwhile the bow equipment was not developed for adjusting shooting angles in Kyudo.
As explained above, the bow equipment have developed differently between Kyudo and Western archery, along with purpose, environment, and so on.