Was his prediction fair? I think it was fair.
I think he was wrong with this prediction. This would be equivalent of a Bitcoin market cap of more than 200 trillion USD.
The US dollar is the dominant payment system in the world. But the US dollar's M1 supply is about 18-20 trillion USD, even M3 is just over 20 trillion. A market cap of 20 trillion would result in a $950k-$1M Bitcoin. I think this is more realistic as a long term target price, but it's not guaranteed at all.
A 10 million USD bitcoin imo can only be achieved if Bitcoin becomes the only relevant payment system, currency and store of value in the world. For several reasons I'm not convinced by this scenario.
There are plenty of reasons to be skeptical about the predictions, I think the impact of decentralized control systems that no country's government has the ability to control. Or to be a relevant payment system all fiat in the world would have to be killed, even the dollar.
Almost sixteen years ago Bitcoin had no value and in that time the last ATH was $108k in last month. I think Bitcoin deserves a big boost moving forward.