You could retire off 500,000 I guess but only if you live frugally and what's the point really?
You're forgetting taxes which will eat up 20% ( if you're long ). Leaving you with $400,000.
With an 8% a year growth you're looking at a yearly income of <$40,000 pre-tax... And running the risk of course of a few bad recession years destroying you all together.
Very easy to squander 500k if not working. Look at lottery winners majority are broke and in poor health. Stay employed my friend or create jobs. be a part of life..and enjoy this wonderful life we've been givin.