The horrible exploitation of labor during this period is what gave rise to Unions and the "Progressive Era."
The "horrible exploitation of labor" is what gave rise to the US as superpower and developed world society. And I doubt labor unions and the "Progressive Era" would have had much traction without the high demand for US labor spurred by the Gilded Era.
It's remarkable how poorly understood and interpreted the Gilded Era is. Somehow they built up a superpower, a vast economy, a set of world-class universities, and the current modern medical system. Yet it's supposedly all bad because labor was exploited. Well, China isn't going to get a shiny developed world society without a vast amount of labor exploitation any more than the US could.