The @axe-core/react npm package is still at v4.0.0, when 3 releases seem to have been done since.

$ npm search @axe-core/react
NAME | DESCRIPTION | AUTHOR | DATE | VERSION | KEYWORDS
@axe-core/react | Dynamic… | =npmdeque… | 2020-08-25 | 4.0.0 | accessibility a11y lint test
Thanks for letting us know. We're planning on getting a release of all axe-core modules with the latest version of axe-core out soon.
We just released all axe-core-npm (@axe-core) with the latest axe-core v4.1.1.

The versions of axe-core and @axe-core packages are not guaranteed to be the same. In this case, the version released of all @axe-core packages is v4.1.0, which uses axe-core v4.1.1.