ISP's in the United States have a long history because they are essentially the same companies that brought telephone and telegraph service to the US over a century ago. The major telecom companies today were even once a single entity called the Bell System or more commonly known as the American Telephone and Telegraph company (AT&T). The Federal government forced AT&T to breakup at the conclusion of their anti-trust suit (United States vs. AT&T). however, the government has failed to enforce this breakup and AT&T currently controls many of the companies that they were forced to divest.
This obvious corruption and monopolization is common with all the major ISP's (AT&T, Comcast, Verizon, Cox). This can be seen in the various lawsuits brought up across the country to limit what new startup ISP's can do with the existing infrastructure. When even Google/Alphabet is having struggles starting their own ISP, that's a clear sign that there is definitely a problem with the way city, state, and the federal governments regulate the telecom companies. With the passing of the Telecommunications Act of 1996, new entrants were supposed to be able to lease access to the utility poles that the incumbent telecom companies' control, but obviously that has not been the case.
So, I'm going to go into some more detail on how the market currently stands as well as how it became that way.