I've just diagnosed a friend's linux mac which had stopped booting from disk. And, of course, a WIP MSc thesis is stored on it!
OpenBSD's installer could boot on the mac from USB but the only disk showing up in dmesg was the USB stick. It's a spinning disk and it made no noise.. First diagnosis: patient deceased.😭
But there's a happy end: Put the disk in a USB-to-sata tray and tadaa 🎉 it works and files can be read!
Disk doesn't boot in a thinkpad either. Maybe bad boot sector? UEFI fuckup?
In any case I am getting all data off this disk ASAP.