I personally believe that Prettier strikes a decent balance between being configurable vs being opinionated. I've used formatters that are much less opinionated than Prettier (e.g. the last time I used XCode it only handled indentation by default). ESLint also teeters on the edge between configuration vs convention quite well in my opinion, especially given the fact that browser JS and server side JS have vastly different linting requirements. I also love the extensibility of ESLint. Being able to write your own linting rules is a boon on productivity. Having access to custom framework specific linting rules is quite nice (I couldn't use React without the react-hooks/rules-of-hooks third party ESLint rules).

> Some JS, some TS

I think the JS community has done remarkably well amongst dynamically typed languages in settling on one form of gradual typing and adopting it fervently (Flow no longer has any market share at all). Whereas the last time I checked Python still had the Mypy/Pywright divide, and Ruby had the Sorbet/RBS dichotomy.

Ultimately though, most of your critique boils down to the fact that JS (unlike Rust and Go) isn't maintained by a single monolithic entity, and therefore there's no one to dictate the standards you're looking for. If Deno were the sole caretaker of JS for example, we'd have a standard linter and formatter devoid of complex configuration, but Deno doesn't control JS.

This is a consequence of JS being a collaborative product of the various browser vendors, TC39, and the server side JS runtimes that have adapted JS to run on servers. The advantage of this of course though is that JS can run natively in the browser. I think that's a decent tradeoff to make in exchange for having to wade through dependencies with different ideas about when it's appropriate to use arrow functions.