> The only reason most people used CS was short hand function declaration and classes
And for loops (which double as list comprehensions). And the existential operator. And "this." shorthand. Among other reasons. To my team it's also more clean-looking than Python (which used to be my favourite language), esp. when using a good syntax highlighter like Atom's (or at least that differentiates function calls, like Github's).
Yes, there's not much difference now from ES6 regarding features, but for some of us it's still worth it.
All these things are irrelevant today.
1/ Most of CS features are supported by javascript
2/ ECMASCRIPT spec is big and complex. Learning another syntax on top of something every front end developer should know is a wasted effort in my opinion.