By the time some small electrical grids were bringing electricity to houses in the 1870's, there was a diversity of lighting available. Candles were being used- but they were not the same ones that would be used circa 1700. They could be made with paraffin as well as beeswax, and were produced in factories like many other commodities. So they were far cheaper than they had been: "The game is not worth the candle" actually meant something in the 1700's. If you stayed at an inn, you would be charged for the use of a candle. But even in the 1700's, there would also be oil lamps and rush lights, that were cheaper sources of light than candles And there would be expensive candles, made from beeswax, and cheaper candles, made from beef tallow, that smoked and melted easily . And after 1800, when the whaling industry had grown and lots of whales killed and processed, there would be whale-oil lamps and spermacetti candles. And, after the petroleum industry started circa 1850, kerosene lamps and lanterns would become the common sources of light, and in some houses with acetylene generators, there would be gas lights.

So, you could say the candle industry suffered little. They were already not that important for lighting, and had become cheap enough to be just another common commodity.