Repeating the argument does not make it more correct. If you're trying to contradict the idea that government regulations are not a large barrier to entry you might show some evidence, preferably in the form of a peer-reviewed study. Your study should also compare the externalized costs of not having said regulations. Even better would be to admit that you've been drawn into a ridiculous position and exit the conversation with as much grace as you can muster.

"contradict...not...barrier" is a triple negative, too much work for me.

Samuel Johnson springs to mind, but if you'd like, substitute "contradict the argument of my previous post". I would prefer that phrasing, but I've often been disappointed at the tendency of people to take issue with small ambiguities or details at the expense of the actual argument.