On the one hand, I completely appreciate this. When I set up NTP, I'm careful to think through consequences and tread lightly. After all, I learned my sysadmin skills at a university before the September that Never Ended, so it really was a collegial place back then.

On the the other hand, the internet is a much bigger place. Things are orders of magnitude more complex. The feedback loops that made NTP work well in a 1990s university environment are mostly absent. When a problem happened then, I'd see something in the logs or in packet captures, figure out what was happening, and get the responsible person quickly on the phone. That's not even hazily possible these days.

As much as I'd love to think putting a stern warning in textbooks would fix this, I doubt that would matter at all. What we really need is a major increase in observability or traceability. And failing that, what we'll get is common resources getting sliced up so they fit within domains of accountability.