Calm down the first certified USB 3.0 consumer products were announced January 5, 2010, at the Las Vegas Consumer Electronics Show (CES), including two motherboards by ASUS and Gigabyte Technology.'''
So when your laptop was on the drawing board and being manufactured USB 3 was a slowly evolving idea.
There's power differences between USB 2 & USB 3 so an adaptor is not a possibility... However there is a solution but it's cumbersome for a laptop.
You may wish to take the money you'd spend on it, and what you can get by selling your old MBP and buy a new one that supports USB 3.0
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