The main reason for restricting lubricant types for VRC is to reduce the chance that it could leak on the field tiles and damage/alter their properties permanently.
For IQ, lubrication is, probably, not necessary because plastic IQ parts have low enough coefficient of friction, robots weight less, and in general you don’t push your designs to the edge powerwise as much as VRC does.
Also, WD-40 is not recommended for plastic parts anyways, since it contains solvents and may damage them in the long term.