But it would require the person to actually take the decisions and to lead. An average employee working on an innovative product doesn't fit the definition.
I agree that it requires one to lead and take decisions. I am not limited to the usual definition. I want to know if you agree or disagree with the usual definition.
By the way, leadership reminds me of an excellent essay, Solitude and Leadership by William Deresiewicz: https://theamericanscholar.org/solitude-and-leadership/