ECMAScript community is actually dipping their toes in the water of adding typing to the spec, and it's at Stage 1: https://github.com/tc39/proposal-type-annotations.

Now of course, this would only add type syntax to the language, not true processing: there's nothing in the spec about actually handling them. Still, it's a step in that direction, so I wouldn't say "very unlikely to ever happen" ... "still a long ways off (if ever)" would be more accurate.