The nominal 5.5 mm OD of the eyelet turns out to be 5.45 mm and fits neatly into a nominal 5.3 mm hole laser-cut into either PETG or laminated paper:
The holes are 5.1 mm on one end and increase by 0.1 mm.
The eyelet fits loosely into the 5.4 mm hole, snugly into 5.3 mm, and only into the 5.2 mm paper hole.
So the nominal 5.3 mm hole is really 5.45 mm, which means the beam adds 0.15 mm to the hole diameter, about 0.08 mm to each side.
Given that the eyelet isn’t quite round and the holes aren’t exactly glass-smooth, figuring a 0.2 mm kerf seems both reasonable and easier to remember.
Obviously, the results will differ depending on what’s being cut, how thick it is, and probably the phase of the moon.
Those are the easiest holes I’ve ever made …