"Go To Definition" for named exports works differently between JavaScript and TypeScript?

Question

Given a file structure like this:

├── main.js
└── util
    └── stuff.js

And some contents like this:

// stuff.js
export function add(a, b) {
    return a + b;
}

// main.js
import * as maths from './util/stuff.js'

maths.add(1, 2)

When I attempt to use Go To Definition on the call to .add() in main.js, I am able to see the function signature as well as any types used in JSDoc for code completion and type checking. However, when I attempt to Go To Definition on it, I see the loading animation at the top of the window forever. Default exports seem to not have this problem.

I figured I'd see if this happens in an actual TypeScript project as well, but renaming the files to .ts makes Go To Definition work as expected. Is there something with the language server that prevents it from working when it is a .js file, despite already knowing about the JSDoc? For reference, here is the jsconfig.json I have right now:

{
    "compilerOptions": {
        "target": "es6",
        "module": "commonjs",
        "baseUrl": ".",
        "paths": {
            "@base/*": ["base/*"],
            "@test/*": ["test/*"]
        },
        "checkJs": true,
        "jsx": "preserve"
    },
    "exclude": ["node_modules", "**/node_modules"]
}

I have tried switching the module option to es2015 and esnext just to make sure it isn't that option causing problems.