Description
package.json's exports uses subpath folder mappings (at https://github.com/jaydenseric/extract-files/blob/v9.0.0/package.json#L37), which is deprecated since Node v12.20.0 / v14.13.0, replaced with subpath patterns (which apparently exist since the beginning of exports maps too).
See https://nodejs.org/api/packages.html#packages_subpath_folder_mappings
The main difference is that the required paths have to exactly match, whether you use require() or import to get to the subpath (whereas with subpath folder mappings, the file extension will be automatically added when using require(), but not when using import).
Fwiw, see rollup/plugins#684 (comment) for the details of the Node algorithm applied to the specific case of require("extract-files/public/extractFiles").