From the article, it sounds like CVUSD isn't an independent organization. The school districts where you live might be structured differently, so this might not be apparent to you.
In Texas, school districts are independent entities (ISDs) with their own taxing authority. The ISD owns the land and runs the schools. Board members are elected.
In Louisiana, where I lived for a while a long time ago, the parishes run the schools. There's a school board, whose members are IIRC appointed by the county commissioners, good ol' boy style. The schools have no tax authority and have to go to the parish for money or infrastructure requests.
It sounds like California organizes school districts more like the latter than the former, though a given county might have multiple districts instead of just one as in Louisiana parishes. The article describes the county limiting bandwidth use by CVUSD, something impossible to happen in Texas as the county has no authority over the ISD.
Likewise, and to your point, the article says that the county encouraged CVUSD to deploy the iPads, and from that CVUSD assumed the county had enough bandwidth to manage this. I guess that means the county is the district's ISP, and the district isn't allowed to change ISPs or contract with a private ISP. And the county IT maybe didn't know the district was going to do this, so they couldn't point it out and try to get a bigger pipe at that level. So they didn't see the problem because bureaucracy.