Do all of these areas who want to be independent of the larger nation understand the $$$$$$ it takes to run a country? it requires its own military, offices, diplomats to other countries and so on. There would not be as much money left over for the people as they were used to before. Why can't the Catalans set up discussions with Madrid and learn to live together perhaps with some new 'perks'? Separating from  the larger country is just ghettoisation or tribalism, and produces what? Poorer countries-- that is what. Do visionaries really think Serbia, Croatia, Kosovo etc are any richer by leaving the larger country?
Catalonians would have to work much harder to keep that economy going---foolishness all round.