This is because the way the telecoms provide coverage data, which the FCC has typically been too scared to challenge because of the revolving door of politician to telecom employer (pretty much every FCC head has joined a major telecom, or telecom related lobby after leaving office for a shit ton of money), and they don't want to rock the boat.
Surprisingly, the current FCC head appears to have a pair of balls... although they are small, at least he is doing more than anyone else ever has.
As for why the offerings appear better than they really are. The telecom industry counts an entire zip code as being serviced as long as 1 property in that zip can get service from a particular ISP. Obviously there is usually more than 1 property getting service, but the telecoms typically cherry pick the most profitable areas in a zip, and provide them with service, and leave the rest to rot. in some cases that means maybe 25 to 50% of a zip will have actual service, but the in the numbers game, the entire 100% is counted as being serviced.
It makes things look really rosy, with lots of competition which in reality is non existent. The ISP's protect there actual broadband deployment data secret, even from the feds claiming it would harm their ability to operate. To some extent that would be true, seeing as the gov would see what is truly happening, and that would allow smaller communities (which these laws currently ban) to build out their own infrastructure.
As for all the others in the entire thread claiming this is about the gov running the internet, well, that is typical political posturing. This has absolutely nothing to do with gov control.