In the future some amount of countries will probably become the same thing. It happens because nowadays people usually promote their own cultures in different social networks and forget about traditions as long as they prefer modern technologies. Most of the people whose try to save old rituals are from older generations.
In my opinion, we should use the opportunity to make our cultures to stay unique.
The reason what we need it is that our cultures make our mentalities are so different, so two persons with an absolutely opposite personalities can choose that country, that will suits them with them mentality perfectly , however if we have the same culture people around the world will must try to act alike because society will became more strict, and might be depressed. Our lives also can become duller and more boring without variety of cultures.
But in the other hand, sometimes boring means safety.The global culture would solve the huge issue of racism. All arguments about culture and historic roots and wars will be ended . So if we had not so many differences we wouldn’t have that much disputes.
Finally it’s a tough call, should we live in the calm, bring world with our cultures that look alike, or in the bright world with variety of cultures but sometimes full of misunderstandings. I prefer the idea of the world where all countries are so different but nationalities respect each other.