I'm not really sure what the author is getting at. You need discipline to avoid most of the garbage that can be created by using any language or framework.

I've seen some of the worst java apps before, but no one says "never use java, it's bad".

It's generally accepted that skilled engineers can make clean, easily maintainable apps, and unskilled engineers make garbage apps.

This just sounds like sloppy engineering and a total lack of professional rigor and in that case, why is javascript to blame?