Supports… some ESLint rules. It is not “easy” to add support to Oxlint for the rules it does not.
The projects at my work that “switched” to it now use both Eslint and Oxlint. It sucks, but at least a subset of errors are caught much faster.
Oxlint does support core rules out of the box but has support for JS plugins[0] as mentioned. If you don't rely on a custom parser (so svelte or vue component for example) things just work. Even react compiler rules[1].
[0] https://oxc.rs/docs/guide/usage/linter/js-plugins.html [1] https://github.com/TheAlexLichter/oxlint-react-compiler-rule...