Alright, a lot to unpack with this article. Let's get started. In a single paragraph Rep Creagan throws out these three statements:
1 - Steel on steel "is 19th-century technology and is obviously very expensive"
2 - "The planned capacity of the line is low with no express train lane" and
3 -  "The number of riders is likely way overrepresented"
Rebuttle:
1) First of all, steel on steel is not so much a technology as it is a choice of material interface between the vehicles and the right of way, just like rubber on asphalt (both of which also come from the 19th century BTW - with rubber tires being invented in 1888 and asphalt paving in 1870). Secondly, it is not the choice of steel over rubber and asphalt (or concrete) that makes the rail project expensive. The vast majority of the cost of the rail is in the construction of the guideway and stations, along with all of the work required to move underground utilities, buy parcels of land, planning, engineering, etc.