Virtual 20 MOA 100 yard zero

Why would the cant of 20 MOA of reticle be anymore error than 20 MOA of cant from a base?

You’re achieving the same result…just one uses a canted base and the other uses the reticle to simulate your base being canted.
From one of the old-timers - Bruce is an optics SME (IIRC, he has a PhD in Optical Engineering) and owns https://highpoweroptics.com/about-us/
20 MOA.jpg
 
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