That is not what will happen. Exchanges will face a liquidity crisis and the price will squeeze up. Instead of denominating in whole Bitcoins, exchanges will denominate in Sats by default and the issue of liquidity will be resolved.
We are closer to that point than people might think. When volatile moves happen, you always see exchanges run into different issues like withdrawing. I don't think this is out of malice, I think this is because there is literally no liquidity left and they have to wait for their market makers to get more liquidity.
Even if everyone could only own one Bitcoin, there still isn't enough for "the rest of the population" to own 1 Bitcoin, whoever said that on CNN is a fudtard.