In my opinion, the Progressive Era had positives and negatives things, they are connected. The positive things depended of the negative things, and vice versa.

Positive Things:

The great wave of immigration from Europe provided “cheap labor to support the rapid growth of major industrial centers and settled in densely-populated urban enclaves.”

Negative Things:

Extensive exploitation of child labor

Overall, it’s a neutral status. It is good to have people come to America help the growth of industries, but they should work on good conditions.

http://www.eagleton.rutgers.edu/e-gov/e-politicalarchive-Progressive.htm