Earlier quoted context omitted.
It's not so different from writing a Qt app in python. The C code does all the heavy lifting with JS doing the UI bits. That setup is way faster than the DOM because the JS is manipulating native widgets. While that's not as efficient as writing everything in C, it is much faster to write and bugfix and results in more stable and secure code.
I've no problem with javascript being available for desktop development. More power to javascript devs! What I find mind-boggling is that a mostly unstructured, dynamically typed and unsafe language is pushed as the MAIN language for desktop development. Has the world gone bonkers?
True dynamically typed code does type checks at runtime which means that performance may suffer, but you are guaranteed to never have critical type failures (the type errors will occur and throw before something actually unsafe happens). This is a huge step up from C which is weakly typed and even untyped via void pointers.
Dynamically typed code is still typed. JS is not an unsafe language from a type perspective and from a security perspective, it may actually have the safest language implementations ever created.
If we're leaving the dynamic scripting language zone, options are very few without becoming tightly bound to Oracle, Microsoft, Google, etc. There are other great open alternatives (for example, SML would be faster with a great type system), but most of those have small communities (which can mean death to open-source projects).