M3, to answer the second part why AI won't be of much help, onwards use a massively different GPU architecture that needs to be worked out, again, from scratch. And all of that while there is a substantial number of subsystems remaining on M1, M2 and its variants that aren't supported at all, only partially supported or with serious workarounds, or where the code quality needs massive work to get upstreamed into Linux.
And on top of that, a number of contributors burned out along the way, some from dealing with the ultra-neckbeard faction amongst Linux kernel developers, some from other mental health issues, and Alyssa departed for Intel recently.
Seriously though, it does seem a menial task in itself to reverse engineer what's going on. Would be a really powerful show of force by one of leading AI providers if they setup shop like that to do it in the open.. if they could.