According to the reports I found, there were 1,055 IPOs in 2016 with a total value of $132.5 billion. Those are global numbers — the entire world.
If he took 100% of the value of those companies and split it evenly between the 7.5 billion people in the world, we’d each get $17.66. But I don’t think he’s talking about taking 100% of the value of those companies. He said it as “taking a portion”. So if that portion is 10%, each person would get $1.76/year. And those numbers assume that the value of the stock didn’t go down after the IPO. If any did, then the amount to distribute is even smaller.
He was talking about Greece specifically and Greece had no IPOs in 2016 at all. So there would be no revenue for them to distribute to anyone.
These faults with it seem to obvious so there has to be more to his idea than what was presented. If you happen to run across a further explanation of his idea please let me know!