I think the point is that is doesn't say "map", is just says "sufficient nav data" which most have interpreted as "map". Since most aviation law seems to be acquired from clubhouse gossip instead of reading the actual rules this kind of thing becomes common belief
Shunter, should you read the actual rules rather than rely on clubhouse gossip, you'll find that the UK ANO does indeed say "map", not "sufficient nav data"! From Schedule 4, Scale A(2), which is a legal requirement for flight by all aircraft registered in the UK:
"Maps, charts, codes and other documents and navigational equipment necessary ............... for the intended flight of the aircraft including any diversion which may reasonably be expected."
However, these items of equipment do not need to be of a type approved by EASA or the CAA; and nowhere does the ANO specify that they have to be in
paper form.