There is one company not mentioned: Filmotec in Germany, better known for it's old brand name ORWO. These guys produce b/w motion picture films like the ORWO UN 54, a viable 100 ASA film in fact, without rem-jet and at least as good as Kodak's b/w motion picture films. Some people buy big rolls from dealers like Wephota or Wittner Kinotechnik and roll their own 135/36, probably one of the cheapest ways to feed a rangefinder or SLR.
Part of this is due to the antistatic properties of rem-jet. At high speeds during printing or filming, static electricity can discharge and fog film. Rem-jet is conductive and dissipates any charge. B&W films are now coated on a conductive stock that contains a small amount of conductive material.
In addition, rem-jet is very neutral, a must for color film.
In the early days of coating, B&W film made one pass through the coating machine, but color films made up to 7 passes. The statistical chance of increasing the static discharge problems was probably large. IDK. Color was also coated at higher speed due to the number of passes. And, as I said, rem-jet is very neutral in color, thus being ideal for color.
It may be that some early B&W films had a rem-jet back. Again IDK. I have no idea of the history of this backing. I would have to talk to a process historian at GEH.