This is not uncommon. Usually a product "family" is all from the same wafer. During packaging and testing either certain pads are not bonded out or certain fuse

This is not uncommon. Usually a product "family" is all from the same wafer. During packaging and testing either certain pads are not bonded out or certain fuses are blown out (via laser cutting, or as an efuse) to disable certain features that are not available on the lower end version. In this case Intel is building certain accelerators for some of its customers, and enabling it only for them before shipping it out. I don't think any of these cores contain trade secrets, rather specific functions they've requested which helps accelerate their stack.