I believe this El Paso line is a partial restoration of a PCC car line that used to cross the border until the 1950s, no?
I wouldn't quite call it a restoration, as it uses all new track and infratructure, none of the infrastructure of the combined Juarex-El Paso system seems to remain. Also I am not sure that the particular cars used ever ran the international route, as they were first built in the late 30s in California, and only later bought by El Paso in the 50s. They may have arrived just too late to run over the bridge.
That said, I do hope El Paso comes away from the experience enthused to build out more transit - while it is a very car focused city, geography pinches it in away that make rail corridors not too crazy, espescially something like a heavy rail commuter line running up to Las Cruces. The city would do well to eventually connect across the border again, but in the current national political climate I can't imagine trying to get funding for 'subsidized public transit to bring people from Ciudad Juarez straight into the heart of an american city", even if locals on the ground know that cross border trips and commutes are a vital part of the Jurez-El Paso metro area.