Lots of comments are misunderstanding the point of the map and think it's supposed to be perfectly accurate. No, that's not at all the point. The point is to allow individuals and businesses to challenge telecom self-attestations of coverage that are likely suspect. So if e.g SpaceX says you're currently served by Starlink but it turns out Starlink is refusing you on their site until the middle of next year, you can…
"This map displays where Internet services are available across the United States, as reported by Internet Service Providers (ISPs) to the FCC. The map will be updated continuously to improve its accuracy through a combination of FCC verification efforts, new data from Internet providers, updates to the location data, and—importantly—information from the public."