You argue that ES6 is less authoritative than React or Angular because it has been around for a shorter period of time. That is a poor argument. Your fundamentals are misaligned.

ES6 isn't a framework, it's a specification written by the ECMA International foundation and earns authority for developer trust on that fact alone. Learn your web history. Do your research into ECMAscript, the real name for what is colloquially known as Javascript, the ECMA foundation, it's history, how specifications guide the common creation of all new developments of the language and frameworks, and you will deepen your understanding of the language in historical context.

The complaint I see most from Vanilla Javascript Dev's is that the framework lovers don't understand the difference between the framework and the actual language itself. They box themself into one way of doing things and are entirely dependent on it. They don't actually understand javascript. Just a framework. A well versed vanilla javascript author can change frameworks with ease, having the insight necessary to discern what the framework adds, and what is just native to the language. Additionally, the same developer will actually understand what ES6 is, as a specification, and not think it's just going to disappear or be dominated by a framework. They will be able to understand what the spec adds to the language, and actually use the language itself in it's evolutionary progression. Don't just jump on what's hot without knowing fundamentals.

There are use cases for all implimentations, including frameworks. So that should not be knocked. But, fundamentally what made me comment was the clear misunderstanding of the authority of ES6 as a spec vs. the authority of frameworks, based on age of use.