In their minds, a flight under IFR is always receiving an ATC service, and following some sort of IFR flight plan. No service/clearance --> you can't be IFR.
Hence when they prohibit IFR, they suspect they mean to prohibit flying under an IFR clearance (whether in IMC or VMC).
From a UK perspective, this view is completely misguided. It is still the law... hence the change to allow VFR at night so non-IR/IMC holders can still fly at night.
Reading this, anyone who wasn't brought up on the UK system would think that the lunatics had taken over the asylum here. An "IFR flight", to anyone else, is a flight that is prepared to enter IMC, which customarily requires an IR. It also requires certain minimum levels to be flown, without the strange exemption for visual IFR that currently exists in the UK RotA.
The idea that pilots with no instrument training can fly at night in conditions where they self-separate, do not enter cloud and maintain a minimum in flight visibility looks remarkably like "VFR" to me. It it walks like a duck and quacks like a duck...