Unless specifically trained to do so, humans are generally completely unproductive when they are unable to see. The reliance on sight all our lives as the main method to take in the world around us means that we are unable to function when that is taken away. The invention of different ways to carry around a flame did a little to alleviate those problems, but not at the scale that electrical lighting could ever accomplish.
Larger flames could illuminate large fields, but at the extreme cost of a large amount of fuel and the risk of burning everything down. It simply wasn’t an efficient practice, and productivity in general stopped as soon as nightfall came. The invention of electrical lighting provided a cheap method to continue to get things done even once natural light had faded past the horizon.
While Thomas Edison is taught to many school children to be the de facto inventor of the light bulb, the technology was in development even before he was born. Using heat to cause incandescence in wire was accomplished even before the 1800s, though became more widespread after the turn of the century. James Bowman Lindsay’s bulb created around the 1830s is credited by some to be the first incandescent light bulb, but his other work kept him from ever perfecting his creation.
More than 20 precursors to Edison’s bulb existed, but he remains to be considered the father of light because his version was both more efficient and more economic than its predecessors. This allowed for its usage to be widespread to people from all walks of life. Incidentally, this has also allowed for more consistent sleep patterns, as people living in regions dominated by long nights in the winter developed un-continuous, segmented periods of sleep due to going to bed at dusk, but that’s an entirely different conversation.