I would argue that is still latent demand, just on a geographically larger scale. If demand were met (globally) then adding a train line (or highway, or stroad

I would argue that is still latent demand, just on a geographically larger scale. If demand were met (globally) then adding a train line (or highway, or stroad) would have a neglible impact on traffic and business development patterns - because everyone can already get to their needs and wants in a timely and economic fashion and therefore has at most casual incentive to use the new infrastructure. For instance a literal "road to nowhere" may 'induce demand' but only because there is unmet demand elsewhere.