I don't live in Chicago so my perspective on this is pretty much worthless. I love the location of SF currently, BUT the Bears need an upgrade in a bad way. Fuck history, SF looks like a giant turd compared to some of the other stadiums. Chicago is one of the largest markets in the NFL and the Bears play in an shit stadium. Find a way to build something in the current location and if Chicago Park District (i think that's who owns it) doesn't allow it for whatever reason, then move to the burbs.
I agree though that it'll never get built with only private money. There will have to be some public financing, which sucks for you people in IL. The McCaskeys are billionaires, but will want public tax dollars to help pay for it.