Nobody has yet to create a thread on the NEM forum about the total number of NEM. Are we happy with 4 billion?

no need for discussing the total number of NEM, it was designed in the beginning ,
and everyone accept it.
As an aside, 8 billion NEM will likely have a larger marketcap than 4 billion NEM, because of how human psychology works.
I don't understand what you meant here unless you meant individual NEM would have a cheaper price and this would compel people to buy more. This is a regularly brought up complaint about Bitcoin where people are complaining they can't even afford just the one Bitcoin.