The non-illuminated is a 1 inch tube, and the illuminated is a 30 mm tube. That may contribute - there seems to be some confusion surrounding this.
What would illumination have to do with the small 20mm objective in a 30mm scope?
Nothing, other than it’s two models that share the same designation and magnification range. You have to dig to find that the illuminated is a 30 mm tube.
The VX-R was a 30 mm tube and listed a 20 mm objective also. Maybe the reserve the 24 mm for the VX-5/VX-6 line.
I’d recommend getting John Burns on the case.
He’s around; and clearly bored.