Kk, slow down here. There's too many things that are funky with this.
Not every ADC builds IE first; in fact, I'd say it's roughly half, maybe less than that. Many build Triforce, Blade, or even Bloodthirster first (the last one being in Draven's case sometimes due to synergy between Life Steal and Spinning Axe).
10 autoattacks in a lane trade? That's more like a fight, normal trades with these kinds of items are about 3-4 autos tops. But anyway Bork has Attack Speed, so it would get out the attacks faster (10 for the champ with BoRK, about 6-7 for someone with IE). 2 of those 7 attacks for the IE user would crit, and yes, for decent damage, but Bork would usually still win out due to the Life Steal and %health Passive (which, of course, applies Life Steal) until the abilities used come into account. From there moreso than ever it is largely dependent on the champion in question, NOT what they build.
Vayne actually does trade early when the situation is advantageous. Granted, those situations don't come often but in short trades, depending on the abilities from the opposing ADC and whether or not she avoids them, she can outmuscle a lot of the bot lane meta in that fashion, thanks to Silver Bolts and Tumble's autoattack reset, which is something that every other ADC not named Sivir wishes they had.