I was affected by the throttling. After many years of paying for an unlimited plan and using an average of 1.5GB, one single time I went over 5GB and got throttled. That sent me on a path that ultimately made me switch to T-Mobile with whom I'm quite happy. One of my justifications to stay with AT&T was the unlimited plan that kept being grandfathered, but what good it is if it gets throttled badly past 5GB. Customer support refused to remove the throttling for the few days left on my phone cycle. I saw no use keeping an old plan without texting and limited voice minutes considering the unlimited voice and text plans prevalent now. Always worried about overages on my other lines.
Now AT&T cannot claim it didn't affect customers or that it was well advertised. It did affect me and I hope they pay the fine and don't get away with this egregious practice.
If you are not happy with AT&T or Verizon, and you are not happy with their plans, or overages I would encourage you to give a try to T-Mobile. It definitely is a more fun ride with John Legere's antics.