The overwhelming majority of front-end projects and developers that I encounter use some kind of library, framework, or compilation/build tool. It's common enough to basically be the default.

If you use 'plain' or 'vanilla' javascript (or CSS), you're doing something less common, at the very least around these parts, and so qualifying this makes sense. The mere fact that many people clearly seem to feel a need to point this out makes it so. Why would they otherwise?

Judging by your comment history, the vast majority of your contributions here boil down to some kind of dig at how 'people these days' are 'doing it wrong', and how obviously you are superior to that and how you don't see the need for any of this new-fangled stuff. I'm honestly curious whether that's just role-playing, or if that kind of superiority about being older and wiser is somehow important to you.

I'd very much prefer it if you shared the wisdom you've accrued in a more constructive way, because as far as I can tell you're not actually wrong about a lot of this stuff.

Older and wiser curmudgeons have played a valuable role in my development, but your approach strikes me as self-serving and somewhat poisonous to the/any community. But of course you're free to do as you please.