You never know, disks are picky (SSD/HDD), and SATA cables too. I know because one of my Xen setup failed on me recently. That’s why I prefer ZFS than ext4/UFS/LVM, it’s more reliable in my experience.
Anyways, time for a backup ! From what I read, Qubes made that quite easy, and since at least 2015 ^^
PS: when I said unbootable I rather meant a boot error, like during kernel/system init, not a disk/system failure, dunno if I’m clear.
Maybe it works for them and it’s just your (hardware) config which makes it hard on you. Also, isn’t that a good collaboration model ? ^^ They provide things and in exchange you provide feedback !
Slightly off topic about documentation
TBH, I’ve not read ALL the Qubes docs, and I quickly read HW requirements, but I find it quite dense already, and very well written ! Maintaining up-to-date documentation WHILE developping and debugging new features is a time-consuming thing.
By the way, you can contribute to it ! I started. Not only you will make the project better, but you will alleviate some burden from the Qubes team, allowing them to focus on other things. Also, you may learn things just by contributing.
For example, when I started Xen (4+ years ago), I only had the kind of outdated Xen wiki, and had to do WAY MORE external research than i had to do to make Qubes work. Except for the problems related to the way I’m testing it (nested), I don’t really need to do external searches to the net to find answers, the docs and the forum are enough. But I admit I have MANY (new) features to try yet.