As a JS dev, Cofeescript appeared to be nothing more than an attempt to make JS more like Ruby.
From this perspective, TS appears to be nothing more than an attempt to make JS more like C#.
Either way, both appear to be attempts to use JS's massive flexibility to make the language work more like another language, because people are more familiar with that other language. And in both cases, there's a familiar response of "please don't do that. Please stop complaining about JS because it's not like your favourite language. Please learn to use it properly instead".
I played very briefly with CS to see what the excitement was about, and haven't touched TS at all, because I enjoy JS. But with Vue moving there, I think I'm going to have to bite the bullet and take a look.