I saw the best minds of my generation wasted by coding everything in javascript
We ought to recognize the use cases, as much as humanly possible, for all languages or frameworks or platforms (etc.) and simply use the best tools for any given job.
Well, isn't that a bit of the point the parent makes? It is not necessarily the best tool for _everything_.
(Not criticizing the project, many package managers are written in some scripting language)
I wouldn't exactly consider Operating Systems to be one of those use cases for Javascript. The flip side of knowing the use cases is knowing the limitations and understanding that "everything" isn't exactly a valid use case, which I believe is what larme was trying to say.
I will say, though, that exploring the possibilities for a language is not a waste of time or mind. From stretching both mind and tool to do new things, new insight can be gained or patterns formed that might never have been considered.
Additionally, nobody ever said an OS has to be the best at everything either. It could be that a javascript-based OS, while perhaps not as efficient at generating machine code, may end up being much more efficient for humans. This would certainly be a win for many tasks such as management that should be optimized for human use.
There are a few great features in JavaScript (seamless closures, asynchronism, etc). However, JavaScript has a few flaws as of today, and even though it's one of the most widely used out there, that doesn't mean it'll work for anything. There are other languages out there!
They may not be garbage-collected, the syntax may not be straightforward, you may need to declare your functions and define interfaces, but they also have great features when you learn to use them.
Any programmer should be able to understand basic C programs and reason with pointers, know how to write simple Java classes (without an IDE) and most of all, use UNIX tools (echo/cat/grep/less at least, pipes being a plus, sed/awk/cut/diff would be perfect). These are basic skills which are taught in CS courses, but many fail to have one of these, yet blabber about Node.js all the time.