> Would taxpayers/stockholders fund it?
And who pays the ransomware when it happens, if not the taxpayers/stockholders? Or does money just get created out of nothing when needed?
> Would a small business have the cash flow to do better?
IME small businesses can do it if they want to. It takes care, meaning policies, it's not expensive. Also small businesses are less attractive to large criminals.
> If they were told it was secure from the tech folks, would the non-tech folks have any way to prove this wrong?
If they got publicly ransomed, it would become very obvious something needed looking at. The process of potentially hammering them legally would involve them being taken to court where their level of culpability would be decided (and it may be they did do enough so get let off, and everyone can see what happened, and other businesses can decide perhaps to up their security based on the results).
These are all strawmen. I'm not asking for uncrackability, merely due diligence. A little of that goes a long way. These arguments don't stand up. You seem to be arguing for... what?