There are two common versions of this. There's "produce the same chip for everyone, test it, disable the bits that don't pass, figure out the maximum speed it runs as, sell things that turned out better for a higher price", which seems quite reasonable for a process with variable yield. Then there's "produce the same chip for everyone, soft-disable features for people who don't pay to unlock them", which seems much less reasonable. (Perfectly legal, and should be, just obnoxious and unpleasant.)
Completely agree. Only issue is that this is based on the defect rate being high enough that enough lower-bin units get produced. Could argue that at that point the price of the higher end units could be lowered a bit, but that might still be outside some people's price range... This seems like a difficult problem to solve in a good way. On one hand it wastes resources, on the other hand it has the effect of the buyers willing to pay more for the higher end models to lower the price of the locked down models further.