"a crash of the web server or kernel"

That rules out 99% of people who are successfully doing the work right now.

It rules out 99% of the people successfully doing something which they claim to be "full stack". They might be great at their jobs, but I don't consider them "full stack". Low-level stuff is always part of the stack.

I guess there has been a sort of grade inflation on "full stack". When I go looking in the "Who wants to be hired?" threads for people, my reaction to seeing "full stack" is that the person is almost certainly exaggerating to an extreme. Real "full stack" is super uncommon, but it sounds impressive I guess. It's just not very believable.

I think you're missing the "web developer" part of the full stack. It means you know all tmthe stack required for web development.

Either way, aren't debugging crashes with c/ASM still taught at uni? Or is the idea of using gdb too much these days?

Crash of the web server => read the log and find where you made a typo in the config file

crash of the kernel => google the last error lines (hope you have one)