It's funny how people come out to celebrate in droves when Apple does the bare minimum to not break their own tooling. Another equally likely scenario is that their changes broke internal tooling, and so they added the raw image mode to give Mac engineers a more reliable entry point for prototyping and testing on the new devices.
Regardless, when my mail carrier changes their route to get to my house 30 minutes faster I don't take it as some sort of sign that the UPS cares about me more than the others. It seems more likely to me that Apple saw the logistical value in not breaking their own kernel requirements with every release, and that happens to be serendipitous with the greater development community as a whole. If Apple wanted to help the Linux community, we would know because they'd be releasing UNIX kernel blobs so people wouldn't be forced to spend years re-writing code that already exists. But of course, that's not how their industry works. If Torvalds gave Nvidia just one middle finger for their treatment of Linux, it's hard to imagine how many he'd like to give Apple these days.