If bitcoin becomes million dollars each, or litecoin goes for 500$ and dogecoin goes for 1$ the sheer number of fiat millionaires it could create in the world could be thousands..
Is this socially possible? yes lot of people have become lot wealthy with lots of bubbles in past, the dot com bubble is a classical example creating lot of millionaires.
So what happens to the world if millions of millionaires are created all of a sudden?
will governments and rich people who have a lot of influence over the world(like Bilderberg), allow that to happen?
Dont forget that in that time, effective value of $ will fall. So, one bread wont be 1$, it's gonna be 1000$ (not exact math, but you get the point). So yes, you will be millionair, but you wont be able to buy as much with that million as you can buy right now. End game situation would be BTC taking over fiat. In that moment you can have 100000000000$ and you wont be able to buy anything with it. As simple as that.
As aditional example, 1 milion dollars could buy you ALOT more 50 years ago than it can buy right now, and trend (value of dollar falling) will just speed up.