inputs.who-to-greet.required should be set to false since the parameter has a default value

[ilyasotkov]

I can use this Action without supplying any inputs and the default for who-to-greet input variable is "World". Why is it documented (in action.yml and README.md) as required?

And more generally, why would Metadata syntax for GitHub Actions specification even allow required: true and default to be specified together?