the idea that there could be less (or about the same) regulatory interference of business today is, frankly, ludicrous.That depends crucially on which business you're talking about. Exceptions abound. Consider that example of the mail-order wine business. Do you know how hard it was to start such a business in the days before FDR? There was a lot of "regulatory interference", personified by guys like "Eliot Ness". You couldn't start a wine business in the USA, full stop -- unless you kept it underground. That era also had a devastating effect on our brewing industry that took a generation to recover from.
One could also ask some of the people who run porn sites about the complex history of "regulatory interference" in their business.
And, as we now know all too well, there have been times when regulation of the financial industry was much more strict than it is today. That's not a simple history, either: Corporations and stock exchanges have existed since the 17th century, but their degree of regulation has changed in complicated ways over time.
And a relentless focus on taxes obscures other forms of interference that were more important at certain times, for certain industries. However onerous it is to start a telecom-based company today, it was probably harder back in those days before FDR, when AT&T held a government-sanctioned monopoly over all of US telephony:
http://en.wikipedia.org/wiki/Ma_Bell
In 1934, the government set AT&T up as a regulated monopoly under the jurisdiction of the Federal Communications Commission, in the Communications Act of 1934... by 1940 the Bell System effectively owned most telephone service in the United States, from local and long-distance service to the telephones themselves. This allowed Bell to prohibit their customers from connecting phones not made or sold by Bell to the system without paying fees. For example, if a customer desired a type of phone not leased by the local Bell monopoly, he or she had to purchase the phone at cost, give it to the phone company, then pay a 're-wiring' charge and a monthly lease fee in order to use it.
That the Internet managed to come into existence at all is the result of a complex interplay of antitrust law, the rise of government-funded research under guys like Vannevar Bush, and the Cold War (DARPA, which funded the Internet, was born in the days after Sputnik).
Today, our cable and phone companies also wield virtual monopolies with the help of the FCC. The situation is pretty bad in the USA. But I'm not sure it's significantly worse than it was back in 1940.