These two things are not exclusive. The language can be deficient, and you can be irresponsible not for using well-known, long-established tools for addressing those deficiencies.
Normally I'd toss in a jab about deficiencies in choosing your language, too, but Javascript gets a bit of a free pass here on the browser.
Oh, certainly I'm not saying that a developer gets a pass for not using everything at their disposal (especially if it's something the developer had a choice on).
But the implicit requirements in tooling, the fact people are blaming a developer for using the language without also relying on third party tools, tells me a lot about the language's deficiencies. Also a bit about the language's community.
Normally I'd toss in a jab about deficiencies in choosing your language, too, but Javascript gets a bit of a free pass here on the browser.