Skimming through majority of what's being said. Look at it this way. This is a NA server.
Now let's take steps back. Every country has their holidays and important stamps on history. They bring them into the game. That's free content and a remembrance of what they lived and survived through. Now let's throw the comments and views of everyone else who wants and expects their country to be included in that countries server. Can you see it? If not then it's ok. You just failed to realize this is not a Canadian, Mexican, and etc. Server. Look at it like this to give u a better picture. You have your culture and now let's smash everyone elses demands for their countries culture to have some priority over your countrys culture. The easiest response is become diversified if there is enough people to make those cultures worth adding. Your own countries culture reigns supreme in their country.
Moving on, the North American servers on many games including PSO2 have extended their reach to other countries allowing them to play legally so they are not left out and whatever else intentions they have. (Hence the "International Server" and other advertisements and notices)
Further along, the game for NA release is still pretty new. Other holidays and events of different cultures are added somewhere down the line. All it takes is enough people to request or reccomend it. Or if the staff had plans to bring them in already. They just need the ok from higher ups and unique/common designs to be made as well.(similar to trying to get a anime collaboration in a game)
Not saying anything you said is wrong since it is your opinions and how you view things. Everyone views things differently its normal. Although parts of what you said is ignorant but that's how discussion start right? A disagreement or agreement then conversing.