No law requires internet providers to run infrastructure to all families’ homes to give them the option of subscribing. Agencies like the Federal Communications Commission have spent years paying companies to run some of this infrastructure to rural areas, mitigating the issue but never completely fixing it.
And the federal government has never really known for sure how extensive the problem is because the FCC has spent years collecting data that underestimates how many people lack broadband, leaving the best estimates to private companies like Microsoft or other nonprofit groups that work with schools.