That's just not true. AT&T's monopoly already existed when the government agreed to let them be a monopoly. The government was investigating them for antitrust violations, and then agreed to stop their investigation in exchange for them doing a few specific things, like requiring them to allow independent networks to connect to theirs in relatively limited circumstances.
Also, it was 1913, not the 30's, when this happened. Over the subsequent decades, the federal government basically gave AT&T everything they wanted - they approved 271 out of 274 buyouts of independent companies between 1921 and 1934, the government did not require them to interconnect their local services to independent local services, they did not require AT&T to interconnect with other long distance providers, and more.
That's the exact opposite of "heavy handed regulation" - that's the government rolling over to everything a corporation wanted.
The two party system is fine, until the parties have the ability to redraw their own districts without any rules as to how those districts should be shaped. Over time, they have to continue pulling farther and farther extreme from each other in order to compete within their own parties, and end up with guaranteed general election wins, which ends up leaving everyone with representatives who refuse to compromise. When you have to appeal to a wide variety of voters in the general election instead, parties end up electing the most extreme they can get away with in a general election instead of a primary - someone who has conviction yet who can compromise. This ends up being a moderating influence in multiple directions - it prevents the parties both from becoming too closely aligned and collude or too far apart to work together.
The solution is to limit the way district boundaries can be drawn - no more districts with a giant tail to add that group of republicans on X highway or the democrats on Y side of the city. Unfortunately, I'm not sure Congress is up to the task right now, which is a massive problem since the problem will continue to get worse, which makes it even less likely to happen...
They're only bad for keeping people working if nobody else has the same restrictions. If every other state had the same level of restrictions, California would be in contention without having to waive rules. If the entire world had the same restrictions, jobs wouldn't be outsourced to third world countries with near slave laborers.
That's the real problem with rules like environmental or worker protections - if only a subset of countries are onboard, companies move to those places where they have more power. If they have the same amount of power everywhere, the laws have no effect on the state of employment.
Your statement, and the sentiment many people hold towards regulation, is ignorant to the facts. You present it as if these companies are choosing between creating jobs and not creating jobs, when the reality is that they're creating the jobs anyway, and they're just choosing where to create them, with a substantial basis in the regulatory environment. Tesla is building a battery factory, they're just not considering California because it's easier to create them elsewhere.