Our project's goal is not to produce an "unsupported hack", it's to make these machines work at least as good as, if not better than, any other machine with "actual Linux support" ;-)
I like Apple hardware (and ThinkPads), but I prefer the openness of Linux (and BSD).
Current MacBook Airs are pretty competitive in terms of price, and the fanless CPU is very appealing. Is it much of a gamble to purchase one now expecting to run mainline Linux in a year or so?
Aside from the new architecture, some components Apple has been using are quite unfriendly. Broadcom wireless cards tend to perform really poorly with open source drivers.
I wouldn't buy an M1 right now... just because the next generation is likely around the corner :-). But yes, I can't promise all the polish or that every single thing will be upstream, but things should be solidly in the "daily driver" category a year from now. I'd be surprised if there was any non-optional (i.e. excluding accelerators - no idea if anyone cares about the Neural Engine yet...) hardware left without usable support by then. GPU is a big question mark that should become clear in the next month or two as I poke at the kernel side, but honestly I expect solid OpenGL a year from now, at the very least.
For the kernel mode part, ANE is behind an ASC.
Some things are dodgier - e.g. though supporting the AMX CPU extensions is quite viable in a kernel fork, I'm not sure if that kind of thing would fly upstream. Same with security features like SPRR - not likely to happen. But these aren't really things the average end user has to care about; they're bonus features, not anything core.
(Put another way: I'm wondering whether you think the difficulty is technical or political.)
I'm hoping we can at least push through a prctl to turn on TSO mode for x86 emulation. I think that one will be simple enough and have enough benefits to convince people.
(The x86 xstate design is horrible. I doubt that ARM64 is anywhere near as bad.)