If I used Twitter…

I’m thinking of writing a novel where human civilization is threatened by a global pandemic, and is then almost singlehandedly rescued by one man … a man who reigned for decades as the world’s prototypical ruthless and arrogant tech billionaire, but who was then transformed by the love of his wife. That is, if the billionaire can make it past government regulators as evil as they are stupid. I need some advice: how can I make my storyline a bit subtler, so critics don’t laugh it off as some immature nerd fantasy?