For me, what Macbeth is about is people who cannot face their fears and pain and instead of facing them and going beyond, they just run away and they try to cover this with power and violence, but it doesn't work.
The real heroes anyway aren't the people doing things; the real heroes are the people NOTICING things, paying attention. The guy who invented the smallpox vaccine didn't actually invent anything. He just noticed that people with cowpox didn't get smallpox.