From what I have seen, the NRLB and the DoL generally have the most solid scrotal metal around. I think they are getting tired of all the corporate double-speak and bullshit as well.
Underfunding and under-reporting most likely. I feel like the advancement of communities online that share their experiences has driven a lot of movement that they didn't realize was as needed as it is. Also, companies are becoming increasingly abusive in their policies and activities.
I tend to agree, which is why I am heartened by their recent behaviors. It also takes workers who are informed and brave. I actively try to make sure my stepdaughter is at least informed enough to know when to call me.