Well if your American Dream is to exploit people, take unfair advantage of them, sell them lower quality products that can hurt them, while at the same time focus solely on how much money you can get from people, then yes regulations may kill your version of the American Dream.
However, if your idea of an American Dream is to be treated fairly, to be able to buy services/products that work and don't hurt you, and for companies to have a balance between pure capitalism and taking care of their workers/customers, than no, regulations won't kill your American Dream.
The issue is that the American Dream is different for everyone.
As we found out in the 19th century, the idea of trusting companies to self-police did not work out so good. Perhaps in the future we may find out that over regulating won't work out so good. I hope we will be smart enough to find out that moderation is always the key.
All I know is that MY American Dream is going pretty good.
I have a good job with a decent salary (not as much as I want, but probably more than I deserve)
I have a good house that keeps me safe and warm
I live in a county with good services which enrich my life greatly
I have a government that keeps me safe from companies (regulations)
I have the press to keep me safe from the government (Transparency and accountability)
I have companies that keep me safe from the press (free market advertising)
Not a perfect system, but pretty good from where I am sitting.
