People that were archers before did it despite not always getting a decent position on the scoreboard. Now we have dedicated archers as well as people who just want to score points while being able to survive easier over the whole course of a round. Longer you survive + longer you are able to put out damage = higher score. People naturally want to play classes that allow you to apply damage from distance with low risk but still good reward. You will see that in every game that allows that playstyle.
Just need more risks for ranged classes, like heavier equipment, having to make each shot count (less ammo, harder to scavange ammo etc), longer time to draw the bow back, longer reload for crossbow, tiring arms if you spam, no arrow stagger, Horse Archery reduces horse movement speed etc. Loads of ways to do it. Damage from range should come at a huge premium in terms of risk. If this were some sci-fi game you know you would have some more player skill based counters to ranged, like manual blocking (hitting slower projectiles out of the sky as they approach). As it is we have to have some realism counters like shields or some other physical cover. Otherwise you just have to make the class hard to play or you will always have this issue, virtually regardless of how much damage the class does.