If we talk about satoshi nakamoto then we all agree he is a genius who can create something useful for the future, which is bitcoin.
Looking at satoshi is genius, it is clear that he will not arbitrarily choose 21M as the maximum supply of bitcoin He must have his own
calculations as to why it must be 21M, only he knows the reason.
Calculations? given that bitcoin was the first cryptocurrency, there are no such thing as calculation on his part cause there are no other variables to consider. So most probably 21 million was just an estimation or the number 21 has a personal meaning to him, though we'll never know it. Another thing is, he might did not choose the number of total bitcoin but is all an accident.
It is very difficult for all of us to guess it. But actually than we are
dizzy thinking about it that clearly will never get the right answer, except satoshi himself who explained it to us all. We better focus on
thinking about something productive, like think of the right strategy to make a profit in the crypto world with bad market conditions like today.
I must agree, instead of talking who the real satoshi is or where is he's at now, let us just be productive on what he did, bitcoin. I'm sure if he's alive until this very moment, he must be proud of the people who appreciates bitcoin. Perhaps he is already dead, no one really knows.