>Aren't there any performance benefits if the class would be final itself?

For instance methods, potentially. For static methods, no. Knowing that a non-overridden *instance* method is in a `final` class would potentially allow the method to be statically bound when called, rather than going through virtual dispatch, but `static` methods *are already statically bound* (hence the name). It doesn't matter whether the class defining the `static` method is `final` or not, the call *must* be bound statically for all `static` methods.