There is a difference between a web site and a web app (although there is blur in the middle obviously). A web site (e.g. this site, a news paper, a blog, a search page, a job application form etc) should not need JS - and frankly if you put it in there then you're over-engineering things. Meanwhile web apps like e.g. Google docs/Office 365, a webmail client etc are clearly going to need specific JS.
You have a failure of understanding here.
There is a difference between a web site and a web app (although there is blur in the middle obviously). A web site (e.g. this site, a news paper, a blog, a search page, a job application form etc) should not need JS - and frankly if you put it in there then you're over-engineering things. Meanwhile web apps like e.g. Google docs/Office 365, a webmail client etc are clearly going to need specific JS.