Physics

Dust in the air and on surfaces will absolutely pollute the condensation.

Pure H2O is nonconductive, it's the impurities in water like salt and the like that make water conductive.

As another post stated, take water, add dust and you have a conductive fluid

Condensation isn't distilled water. The air is a mixture of gases, and those gasses mix with the water.

Any contamination (even CO2 from the air) will make it conductive enough to cause corrosion, eventually ruining the circuit board. Once this corrosion starts, it can add metal ions into the water, further increasing conductivity, leading to more corrosion. If you've ever tried to build an electrolysis cell you will know how good water and electricity are at dissolving metal. (Even thick wires can disappear in minutes)