Not just non-Apple devices. I have a machine with older MacOS and the current Apple keyboard doesn't report battery status. I can't think of a reason why that would work differently from Apple's own older keyboards, but it does.
I think the passthrough is more useful when there's a VR OS to take advantage of it (map your real room/hands/kb/screen onto VR, let you pin stuff, etc.) and I'm not sure Valve is even planning to do that, or anyone is on the Linux side of things (?)
The main reason I voted against was because it is tied to smartphones with only the vaguest promise that it won't stay so. Ironically one of the arguments in favor was independence from megacorporations (or foreign countries for that matter). But you couldn't find this point in the main opposition website. The opposition was very weak with weak arguments and the parliament was massively in favor.
I think a squat format like 4:5 would be much more practical than 9:16 or whatever most phones are. It's unfortunate that's the format that's come to dominate, especially when you consider the rise of vertical video.
The vector version of these is used in antenna theory to represent and transform the radiation of finite sources, like when measuring antenna patterns.