For years the mainstay of mass transit in Panama City was the diablos rojos (red devil) buses. These privately owned, tricked-out buses transported throngs of Panamanians to and fro.
With a new subway system on the way, changes were made to replace the buses with nondescript, modern ones. Loudly adorned, these buses were an iconic part of the cultural identity. So, it's not a shock there was an uproar.
The diablos rojos did not go away and still run many routes. During rush hour, at bus stops in front of the Multicentro, they line up for people leaving the city for home.