Wow, what a long winded way of saying "make my job easier and I don't study economics."
Prople using this scare tactic of "Fees will be thousands!" Don't understand economics. People saying Lightning isn't a good layer-2 are not thinking institutionally. Banks if they want to survive the fiat collapse will become Lightning node runners. Becoming the bridges between vendors and customers. They already have the infrastructure and relationships. 

Diatribes like this are when Coders get lazy and forget they aren't the only important piece of a monetary technology. This is the equivalent of a banking App dev saying that the dollar will fail if he can't get his preferred coding convention to be used in the codebase. Childish. 

 So 21million is enough, even if only a fraction of the population hold keys? 

 News flash: Most people don’t want the responsibility of holding their own keys. If you don’t solve for that, any proposed upgrades to Bitcoin Core to encourage self-sovereignty won’t make a difference. 

 Have this conversation all the time. People can barely manage bank accounts.