AC condensate is moisture in the ambient air that condenses on the fins of your AC's evaporator. Theoretically, it would have no solids at all, except that by the time it travels down your evaporator fins, pools at the bottom of the pan, and drips down the drain hose and into a container, it's already accumulated some foreign debris.
The point is to not use water alone in your cooling system. Coolant concentrate is diluted with distilled/deionized water to form the final fluid that goes into your engine's cooling system.
Coolant lubricates the water pump, raises the boiling point beyond 100°C, lowers the freezing point below 0°C, prevents corrosion, and prevents damage from cavitation. There really is no reason not to use it.
Nobody seems to have read the contents of the image. Only certain regions in the United States have tap water that is suitable (although not ideal) to use in an automotive cooling system, with a solids content of less than 120ppm.
You do not want solids (or gases, for that matter) in your car's cooling system.
