Is the code that Apple is removing support for open source? The Linux drivers could at least plausibly be picked up and used by someone who really wants to, so it doesn't seem to be a fair comparison
Apple's source is not public, but the protocol is still fully documented if someone wanted to create a new client and server. https://developer.apple.com/library/archive/documentation/Ne...
However, they'd be better off just creating a driver and server around the open source Netatalk implementation.