These kind of regulations are instituted under the guise of "protecting the plebians from themselves." So smart investors that don't over trade on margins and have studied TA rigorously to make calculated day trades on pre-determined criteria get punished because some people are foolish with their money, do no DD, then complain and get outraged when their un-calculated risk taking approach crumbles down on top of them. Regardless of whether it is helpful to save people from their own lack of self control or not, the unfortunate side effect is that the big money has an even bigger edge over individual investors. It's always going to be advantageous for whales in any free market, the last thing I want is the government stepping in to take my competitive edge away and delegate those decisions that will be made with my money to the financial institutions.