Manufacturing scale could matter. I could picture a CPU design that had a boot key or other restricted features set by blowing fuses (or similar tricks) during

Manufacturing scale could matter. I could picture a CPU design that had a boot key or other restricted features set by blowing fuses (or similar tricks) during packaging. The "developer" unit leaves them unblown. If they're selling 10M "regular" units per year, and 5000 "developer" models over the product lifetime, you have to amortize the cost of special-casing the production line for a short run, and stocking and supporting a second SKU, over a relatively small sales volume. It could well be more expensive than the few cents of electricity per unit to blow the fuses in a standard unit.