> the owners (or share holders) would not be multi-billionaires, only single-digit millionaires at most.

Mmmm, I don't think your numbers add up...

There are 500 people in the US who have more than a billion dollars. If we made them all "single digit millionaires", we'd be looking at a one time wealth transfer of less than a $1T dollars, or about 25% of the US Federal Budget for one year. Sure, that would make for a good year, but then it's spent and we're back where we started...

I think you're dramatically overestimating how much private wealth there is in the hands of the upper echelon compared to how much the sorts of programs you want would cost.