I'm going to make the argument against trains for everything, despite being a huge fanatic for trains.

Trains are the most efficient transport method per tonne-km over land, yes. However from certain operational standpoints trains can make less sense than existing solutions.

When distance between stops for heavy rail becomes too short, you lose quite a bit of efficiency. Trains themselves aren't a one-size fits all solution as there are various types that each need their own form of investment (which is a lot $), when roads are compatible with both personal transport and large trucks with little investment by the transporter (govt pays for road maintenance).

Rail companies right now are chasing profits and neglecting operational improvements. In the US, hauling a long, LONG, old and slow train loaded with bulk aggregate, oil, grain, chemicals is more profitable than aiming for JIT capability that is more feasible with trucks. A complete change in societal incentives is necessary to bring back the usefulness of railway in all types of transport. Second, the North American way of railroad companies owning the tracks dissuades a lot of innovation and new firms from entering the market, unlike the "open road" where there are many competing OTR freight companies. None of the Big Six would like my idea of a nationally controlled rail/track system.