What are those most extreme case? If you have explained it earlier, kindly link me.

Your calculations are fine like if each and everyone on this planet if decide to own bitcoins then how much they may probably will get kind of thing is what I am getting on first reading. But, if you look for equal distribution then I am sure that you will never have any valid explanation on that and practically that will not be possible as already 11 years has been passed and bitcoin is distributed to around 40 million addys (which is approximate number of BTC addys with balances).

Sometimes back, I have come across a token which was airdropped to everyone and its name was something like mankind or similar to that. I mean that kind of thing alone here after possible if you are still concerned on "equal distribution".