One problem with rail is that there are established companies (often with highly-unionized workforces) that build them. And, at least in some juristictions, lo

One problem with rail is that there are established companies (often with highly-unionized workforces) that build them. And, at least in some juristictions, lots and lots of rules and safety standards, some of them dating back a long time. Building something that doesn't have to fit within railway rules, and which you can build yourself using workers you've hired and trained de novo might well end up looking quite attractive on paper, even if the resulting system isn't fundamentally better than a "normal" railway. The political feasibility of such a project is another matter.