Thanks for the explanation,
Chris.

That makes sense to me.
Sparky,
the AGE of our eyes has a huge effect on our ability so see a bulls in the distance, or see the fine lines of a reticle.
Ask me how I know...!
So, yeah, maybe manufacturers are making thinner reticles, especially for target scopes. However, I would guess(!) that scopes for hunting don't follow that trend (generally, hunting scopes would be scopes with BDC reticles, and those without holdoff hashlines).
And then, maybe the eyes are just a little older....
The following brands, if I recall correctly, publish the line thickness of the crosshairs (there are probably others):
Athlon, Riton, Sightron, Nikko, Sightmark, SWFA, Falcon, some Discovery, some Vector, Riton, Vortex, Bushnell, Hi-Lux.
Matthias