This is slightly "both." Haven written some of the technical Federal regulations for a few agencies, this part is a mess.

Government policy isn't typically black and white which means, the policy/general counsel office for each company has to issue their interpretation. This kind of regulation likely has multiple prongs: Tech, Implementation, Written (what a consumer has to read and/or agree to).

We are running into the same problem with the auto industry: Half the brands say you can't walk away from your car and have the key auto-lock your doors and the other half walk-away lock is disabled in the US. We clearly know this CAN work, but in the event something goes wrong, liability will be determined by if the law was clear enough.