So, I found a way to disable the hashes using node.api.js. It's not pretty and it's rather brittle (especially that url-loader piece), so I would still like to see if perhaps an option could be provided with static.config.js. Here's the relevant piece of code within my app:

export default pluginOptions => ({
    webpack: config => {
        // Not all webpack configs include a hash in the filenames / chunk filenames, so you can't just blindly override
        // these props to static values.
        if (config.output.filename.includes("[hash:8]")) {
            config.output.filename = config.output.filename.replace("[hash:8].", "");
        }
        if (config.output.chunkFilename.includes("[chunkHash:8]")) {
            config.output.chunkFilename = config.output.chunkFilename.replace("[chunkHash:8].", "");
        }
        config.module.rules.forEach((rule) => {
            if (Array.isArray(rule.oneOf)) {
                rule.oneOf.forEach((oneOfRule) => {
                    if (oneOfRule.loader === "url-loader" && typeof oneOfRule.query === "object" && typeof oneOfRule.query.name === "string" && oneOfRule.query.name.includes("[hash:8]")) {
                        oneOfRule.query.name = oneOfRule.query.name.replace("[hash:8].", "");
                    }
                })
            }
        });

        return config;
    },
});

This would actually be the correct way to do this / via webpack options in the static config.

We can turn this into a platform-feature if you'd like (where it would not set the hash in the webpack options).

That would indeed be what I was after. The reason the above is brittle is because it depends on a lot of conditionals, which could grow out of date as react-static evolves. There are other webpack plugins besides url-loader that react-static aren't using today, but could in the future, which may contain a hash of some sort. But, as I said, for now what I have suffices.

Thank you for providing it ❤️