Right, similar experience here, and that's exactly what I mean. For example, I don't think a typical fullstack dev would know what it means to see a 'too many open files', how to debug, or how to fix. Hell, most don't understand the difference between a 'connection refused' and a 'unknown host.' In fairness, they don't have to. I started as a full Linux/C nerd who thought I'd conquer the world, and watched as tools like Docker attempt to make it irrelevant. I say attempt because I find it typically a huge waste of resources as an abstraction, but people love it, so I lost.

I don't feel defeated or obsolete, just the nature of an ever evolving curriculum I guess.

There are plenty of front end engineers that understand how computer works, how server works, and how to debug under pressure.

It's good enough to debug performance and compilation problems.

They exist, definitely.

But I think there are far more front-end developers who know (and are amazing at) CSS, Javascript, react, and all that stuff - and have no ability to diagnose, or resolve server-side problems (be they overheating CPUs, bad RAM, flaky DNS, or other problems).