They know exactly what files were customized in the previous OS-base-image. There’s a reason the whitelist is a whitelist, rather than a blacklist. Just guessin

They know exactly what files were customized in the previous OS-base-image. There’s a reason the whitelist is a whitelist, rather than a blacklist. Just guessing here, but it’s probably something to do with “iteration speed” vs. QA SLAs made to large enterprise customers like IBM. In my hypothetical, there’s a set of preferences overrides Apple have been forced by contract to guarantee they’ll validate during their QA process, and then allow the OS to retain between updates. For any other file not forced by contract, they don’t bother with that QA process (“takes too long!”), and so default-distrust the ABI-stability of the file, and so don’t let the OS retain it between updates.