I think your timelines are a bit optimistic. Realistically, once the federal government has been convinced to start building high-frequency rail, for instance, we can expect it will be at least 50 years before they want to build high-speed rail, in my opinion.
Personally, I think Canadians want high-speed rail and that there is a market for it. I also think Canada's airports are at full capacity and that it will be difficult to use environmental studies to make the case for expanding airport capacity. So it would be better to remove unnecessary flights, such as those between Ottawa and Montreal or Toronto and London, to encourage people to take the train.
That said, I do not think that Canadians and the federal government have the appetite to invest $120 billion to build the system. The government has come up with another strategy, a hybrid rail system, which would travel at high speeds along certain lines. For my part, I would suggest you look at what the government did in France. Between Paris and Lyon, the train will travel at 300 kilometres per hour. Beyond that point, the same train will travel more slowly to Marseille.
The Canadian government could therefore decide, at a minimum, to massively upgrade the section between Montreal, Ottawa and Smiths Fall, which is already mostly owned by VIA Rail. That would mean that all trains travelling between Montreal and Toronto would go through Ottawa. The speed could be increased in certain areas. Heading east, the train would initially travel slowly to Quebec City, at 160 to 200 kilometres per hour. As the government injects more funding, the situation could be improved. That is what we hope for.
That said, if we decide to use the current corridor through Peterborough as it is, we will have problems along the curves because the lines are too narrow for a high-speed train, and much of the expense will be wasted.
In closing, let me make a comparison to Ottawa's Transitway. The planners said they would create a bus system and that nearly all of the investment would be held back for potential light rail. In reality, when the O-Train was built, hundreds of millions of dollars had to be spent to widen the 417 so buses could also use it temporarily. It was a construction site for six years, and nearly all the money invested in the Transitway was wasted to build the O-Train. People say that we could make gradual improvements, but that is easier said than done, unfortunately.