The biggest challenge for VIA over the next 30 years will not be the introduction of HFR as that's really not much of an accomplishment but rather the financial and logistical challenges of de-carbonising the entire network.
Not even close.
1) There's no mandate to decarbonize rail in Canada. This is entirely dependent on technology and economics.
2) VIA doesn't control most of its track. So it can't make policies on decarbonization until the track owners do.
3) With the vast majority of passenger miles being generated in the Corridor, realistically, this is the only portion that will matter for a while. Maybe if Calgary-Edmonton gets built....
4) Time is on VIA's side. Technology is only getting better and cheaper. And the carbon tax is only going to make driving and flying more expensive. VIA can wait for a more appropriate tipping point. Be that in 10, 20 or 30 years.