Hello,
I understand your concern about difficults for each individual to choose the country in which it would want to install.
The problem is that only rich people with a qualified job can freely change of country and nationality.
I understand this because I'm a lambda young with a very low income and that I always dreamed of live Canada for Europe, but I was confronted by some nationalist fools that don't accept that I change of country.
But now, with rise of far right movements everywhere in Europe and North America, it could be even more difficult for the lambda citizen to leave his/her country if he/she is not happy where he/she lives.
The nationalist ideology oppresses all peoples by impose them the allegeance for their own country, and with rise of far right, it could be more difficult for us all to refuse to support our country if it engages a war against another country.
Nationalism naturally favors war between nations and peoples and it's why world citizens need to unite in order to fight it.
Tristan Roch-Desparois