You know, I think I hear from your question, and from the previous question, that there's an interest in thinking about Canadian rail in general, not just the Toronto-Quebec City corridor. I can understand that. Obviously, nobody wants to feel like the national government is investing in just part of the country and not in many other populous locations.
Certainly the rail service from Windsor to Toronto currently, and planned in the future, is completely inaccessible to most people. It's way too slow. The result is that the vast majority of people making journeys along that corridor are currently driving to do so. As I'm sure you know, air service in the sections west of Toronto is also quite poor. Folks are generally driving to make those types of journeys.
It is also true that Toronto is such a large metropolitan area that even though London, Windsor, etc., are not enormous metropolitan areas, the size of Toronto as a huge population centre could make investing in a substantially improved rail service from Toronto to Windsor actually worth it. This would be especially true if there was co-operation with the United States to connect into Detroit, but perhaps that's for another conversation.
Even so, I think it's worth pointing out that yes, that corridor should be considered as well.