Thunder Bay is 500 Km away so at best it is a major airline stop and branch office location on the way to the Ring. Sudbury became what it is today due to the resource being close at hand and not 500 km away.
I'm of the opinion that most of the processing will be done much closer to the ore's source. Cliffs is using Sudbury and Thunder Bay as a bargaining tool with the governments.

What else could mining companies say to a mayor, they need all the help they can get to make things move.

Thunder Bay is a start but if there is going to be a capital of the region in some distant future it just as well could be Nakina or Pickle lake due to closer proximity. Thunder Bay could be delegated to a support municipality as Toronto is/was to Sudbury.

Just my opinion, Ed.