Well the cost will come down eventually, I don't know if it will take 1 year or 100 years but it will eventually.
My question is that the whole planet currently is designed, built, and finetuned for decades around fossil fuel management. These are massive industries involved in one way or the other, with huge and far reaching implications that go beyond the obvious thoughts about company profits, jobs, infrastructure, logistics, service industries, byproducts, government economy etc. This came to my mind from watching a war movie the other day that said the US is spending $21bn every year to protect oil producing areas globally with their military, I mean I don't know if this is true or not but it doesn't sound impossible either. We all think of cutting Govt spending as a good thing, well the reality is sometimes counter-intuitive, it usually just leaves people without income and jobs. And if the Govt spends it somewhere else they're accused of being communists :D
Ofcourse the upside is human life costs, must be millions who have died in history because of fossil fuels.
But what about the countries that oil is their main industry? They will starve.
What I'm trying to say is that even if the whole planet has the best intentions around this, it's a massive shift that needs to happen pretty much everywhere.
And I don't even know if everybody has the best intentions. Not being a conspiracy theorist here, I literally don't know, I can't begin to think whose interests will be affected in what way and what their reaction is going to be. It's just too complicated, fossil fuels are currently weaved into every aspect of human civilisation. Both peaceful and not.