You can learn React in a day. The API is composed of less than ten functions.
To answer part of your question, Promise.js has become formalized in the ECMAScript standard, so maybe not the best example.
These frameworks emerge to make it convenient to solve problems that JS does not offer an easy way to solve. I don’t see anything philosophically wrong with that; in fact, I would argue it’s a big driver of JS adoption. Prototypical inheritance makes it very easy to bend javascript to your will.
If you don’t like the frameworks you don’t need to use them, but it’s going to harm your career if you actively avoid learning how to use frameworks that are deployed with increasing frequency on new projects.
The other advantage of frameworks is that they provide common idioms and enforce procedural standards, both of which make working on a team more productive as everyone has the same base of understanding. They also make it easier to hire for that team.
Try implementing any sufficiently complex app in vanilla JS and you’ll likely end up recreating many of the aspects of popular frameworks, except your “internal framework” will be messy, undocumented, and unique to your project, severely reducing maintainability and increasing onboarding time of new developers.