In my experience, the usage has started swinging the other direction. While in general I agree that ES6, ES7, etc. would be less confusing, it will only confuse people more if the spec is officially called one thing but some people call it something else. If someone wanted to learn about, say, "ES10", they'd have to search for both ES10 and ES2019 to ensure they got what they wanted. I think it's better that everyone agrees to use the official naming scheme to avoid that kind of confusion. But, you know, that's just my opinion.

This is switching and ES2017 is the name we should standardize on to avoid confusion. For example, Typescript accepts targets "ES6" or "ES2015" as synonyms, but it doesn't have targets "ES7" or "ES8", only "ES2016" and "ES2017".

I personally prefer the terse version, but there are advantages to using the year-based naming.