I'd probably suspect PSU last.
do a read-write test to make sure the issue doesn’t re-appear
I can recommend https://wiki.archlinux.org/title/Badblocks
In that case I'd rather suspect the CPU. Decoding video can stress certain parts of a CPU that aren't usually stressed by other applications. YouTube commonly serves AV1 nowadays which most GPUs older than a few years can't decode and is rather compute intensive.
Is the CPU overclocked, undervolted or overheating? Instability in the CPU can certainly cause a complete system crash.
No, the actual issue was an impurity (not working in Nix' pure model). Impurity is a bug; it was fixed years ago.
That being said, the statement that symbol conflicts do not exist on other distros is plainly not true.
I have never claimed such a thing.
Classical distros have exactly one instance of a library ABI's .so in most cases which is usually the only place where any given symbol is defined.
You could technically provoke a symbol conflict using LD_PRELOAD and the like but it's not something you commonly run into because package upgrades always replace the previous version entirely.
You could technically have multiple conflicting sos on classical distros too by prefixing a more detailed version but you don't; doing such things kinda what differentiates Nix from classical package management.
This QT issue in particular was an impurity (working outside of Nix' pure model; not as intended) caused by "installing" qt libraries into your environment imperatively (which isn't something you should do anyways) that was solved a couple years ago.
With the difference that there's multiple Reddits; each with their own set of admins.
Wasn't it a basically unmoderated platform and therefore full of Nazis, science deniers and other social scum that got banned on youtube?
Because other distros usually can't have multiple versions of the same library to begin with.
There's Nickel which is sort of Nix expression language 2.0 but, honestly, the Nix expression language is perfectly adequate for what it needs to do.
Not to say it couldn't be better I wouldn't put it inn any top 10 of what is holding Nix back.
The CIFS errors and logs inside the VMs are rather uninteresting as they're just passing through the underlying HW's issue.
These logs presented here definitely indicate an issue between CPU and drives. Could also be RAM but I'd check SATA cables and controllers first.
Indeed, that looks like a bug. The version field is there but it doesn't appear to be searched.
Could you open an issue on https://github.com/NixOS/nixos-search?
It's almost mythical by this point.