it will certainly not be 3k. I would suspect 1799.A few hundred more than the 16-35 yet still priced under the 14 and 17 TS.
$1799 Bwahahahaha

I've been trying to sell this bridge...you are just the man! :p
But yes, 3K is a tad too high and I won't be surprised if the "I got it first" folks will pay that...but canon likes to not overprice products so high that “aspiration” (a highly valuable commodity in its own right) is not killed among its customers...
In other words, it makes less economic sense to sell 100 units at $5000 (to fools who will buy anything to own something new) than to sell 100,000 units at $2500 (to an average customer). Do the math and you will see that if the number of customers who can afford the product drops off radically, they will gain no major revenue by introducing such a lens.
However, as a temporary measure, sky-high prices do help during the first few months as production may be slow to meet demand and high prices will buy Canon time as they ramp up production....all along gaining revenue from the feeble minded...er I mean early adoptoers...
In the long run Canon will want to move units.
So they will probably price it initially around what they charged the recent 24-70L II ...~$2500 to $2700 for “real” market value not what you see in mark-ups. Within months it may slide a couple of hundreds to get to where other high volume zooms now are closer to the 2.2K mark.