Arbiter has called them bots and bot writers since the start of his project a few years ago. No worries, his time went into great stuff. ;)
Whether OSBot calls their people bot writers or scripters really doesn't matter. In the end it's true that it doesn't directly improve the capability of a bot, however naming things correctly can bring more user-friendliness and cause less confusion. It took me a while to get used to the term "bot" instead of "script" personally, but in the end it does make sense to me.