JSON module imports became baseline: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import/with:

import data from './data.json' with { type: 'json' };

and lazy-load it with:

const { default: data } = await import('./data.json', {
  with: { type: 'json' },
});

It makes sense to use JSON module imports for local static JSON resources where you need all/most of the data within. Particularly since bundlers can understand JSON imports, and bundle the object with other modules. That isn't possible with fetch(), unless you use some pretty hacky plugins.

Generally, I try to turn any "fetch-and-process" logic into a Vite/Rollup plugin, so it happens at build time rather than runtime.