Define "loss" here. As far as I can tell, the Swiss franc is a sovereign fiat currency which lost any association to a gold standard by means of public referendum. The "cost" is effectively zero as it is part of the general economy available to the nation-state of Switzerland, and fits into the larger monetary and fiscal policy of the country.

I have never considered the "cost" of a government service to be representative of anything unless an analysis of social benefits is likewise included. For instance the entire discourse around the USPS during the last US presidential election.

Clearly, the train system is net-profitable for the country or they would shut it down, so calling it a "loss" seems inaccurate.