[pbhjpbhj]

>Technically impossible to give such a guarantee. //

The guarantee is that you won't be charged for service outside of the specifications. That is, an SLA.

In UK airlines and train companies are bound to national SLAs such that if your aeroplane (this might be global?) is delayed by a significant amount [as defined by the SLA] or your train is late you get compensated.

No reason not to have that for ISPs.

The government would need to pair it with a requirement that the ISP can't ordinarily refuse service.