Would you be comfortable citing Wikipedia as a source for coding on an EICR?
I certainly wouldn't.
This is true, but of no relevance.
You cited a dubious source in claiming that control cables are "only to be used for V less than 50" and that is patently untrue. Control cables, as with all cables, are to be used for voltages falling within the cable's specification.
Regardless of whether 95% or 99.99% of control cables are used to carry ELV, they are capable of carrying any voltage within manufacturer's specifcations and for many control cables the maximum voltage rating will fall somewhere within the low voltage band.