I also think this is an overused word....and it makes me cross.
A hero is someone who acts to help others , fully aware of the risk to his own life. An inventor, an entrepreneur, an athlete, a Donald Campbell is not a hero , although he/she may be a great man/woman.
I once had a discussion about this with a WW2 Resistance hero, who never accepted the term for himself. He saved many lives, was captured, tortured, mock executed but he would not admit his heroism because he claimed that he lived in fear, despite his courageous actions. To me. He epitomised the concept of heroism, because he put himself in danger for others, despite his very fearfulness.
He died in the early 1990s.