It's not sprawl, it's that the United States, and by extension Canada, have extensive freight rail systems but almost zero exclusively passenger rail networks.
In Europe and Asia these networks are generally separated.
The American model means that passenger trains need to be built to freight-train safety standards, that a passenger car must be engineered to "survive" a potential collision with a freight train, since that is a possibility.
American passenger trains don't own their right-of-way, and freight companies really don't care about high-speed anything since their business model doesn't require it.
Interesting enough the new version of the Acela trains in the Northeast will not have to be built to those freight train standards. On of the reasons is that the tracks are not generally shared with freight trains in the Northeast corridor.
I recently took VIA rail, from Vancouver to Edmonton. Partway through the trip the attendant announces we'll be 6-10 hours late, which is normal. It hasn't been on time since April. Some daft Europeans with a connecting flight were relieved that we pulled in to Edmonton only 2 hours late! The best in weeks!
In Europe and Asia these networks are generally separated.
The American model means that passenger trains need to be built to freight-train safety standards, that a passenger car must be engineered to "survive" a potential collision with a freight train, since that is a possibility.
American passenger trains don't own their right-of-way, and freight companies really don't care about high-speed anything since their business model doesn't require it.