I'm not sure that's true. If Wall Street really had some super lobbying power Dodd-Frank and Sarbanes-Oxley wouldn't have passed in their current forms. Regulating Wall Street is a pretty easy position to take if you're a politician.
Regarding Dodd-Frank, many people, myself included, believe that that bill was watered down considerably, largely due to the pressure of Wall Street lobbyists. In fact, in the end, a number of Wall Street groups ended up supporting the legislation, largely because they were concerned that if Dodd-Frank didn't pass, then new, more strict regulations would be proposed in the future.
Wall Street contributes gobs of money to campaigns and has some of the most powerful lobbyists in Washington. Considering how unpopular they were in the recession fallout, the fact that the only major retribution was Dodd-Frank is a testament to how much influence the wield.
I think most people agree that over-regulation is a bad thing. What I take issue with is when political groups and lobbyists scream 'regulation makes us less competitive' anytime regulation is mentioned. The fact is it might increase the costs of doing business a little bit, but it also might mean that my air and water aren't horribly polluted (see Beijing air quality) or that I can count on my retirement account actually being there when I need it. I feel like one side is trying to find a good balance, while the other is being completely obstructionist. The end result is watered down regulatory policies that increase the complexity and costs of doing business, while at the same time, being completely ineffective. One major issue with this result is that this greatly benefits entrenched players, as they are already adept at navigating complex regulatory environments (which keep out new entrants) but in the end, they aren't actually affected by the regulations in any meaningful way.
Then our last (hopelessly corrupt) government decided to guarentee all of the bank liabilities when the crap hit the fan. The EU decided that one of these banks was never going to pay back the money (Anglo Irish), and so the money the government had given them went on the national debt. The markets panicked, the IMF were called in, and here we are.
Arguing that it was primarily due to low taxes is somewhat incorrect, while if the tax base had been more diverse the current deficit would have been less bad, we were still really screwed by the nationalisation of banking losses.
I usually don't call for increased salaries for government workers, but the people regulating Wall Street probably need to be making near-mid-six-figure salaries. Otherwise the ones who are good at their job will just get hired away by Wall Street.
What this shows is that Wall Street has America by the balls, and as long as they don't squeeze too tightly, there aren't going to be any restrictions on their behavior.