Bingo. Berlin spent billions centralizing things into the new Hauptbahnhof a few years ago. Madrid is spending billions to connect Chamartin to Atocha as we speak (and built tunnels to eliminate Principe Pio back in the 90s). Off the top of my head, there have also been projects in Antwerp, Malmo, Lyon, Brussels, and Oslo to centralize rail stations. Multiple stations is a historical error places are trying to fix, not an intentional
Agreed. I think there should be several hubs within a city, and a couple just outside of downtown in order to facilitate transfers, but downtown should only have 1 major rail hub. For example, it would be a much better expense to build true hubs at Queen & Dundas (plethora of GO lines, Queen Streetcar (and possible future LRT), and potentially the DRL West), and in Riverdale (pretty much the same deal as Queen & Dufferin). Likewise, Agincourt and Black Creek/Mt. Dennis have a similar opportunity, as does Kennedy.
But Union should remain king, and all reasonable efforts to preserve the transit hub at Union (ie no decentralization) should be undertaken.