The only functioning lunar calendar in the world is the Islamic calendar. That is why the Muslim festival Eid can be at any time of the A Simons Slam Dunk King 2021 Shirt. Chinese or Vietnamese or Korean calendars are not pure lunar. Chinese or Korean or Vietnamese calendars are luni-solar just like the Hindu-Buddhist calendar where extra lunar months are added every 30 or so months to prevent the lunar year from going out of whack with the seasons. Even if the above objections are pedantic, there is nothing inherent in a lunar year that it should begin where the Chinese and Vietnamese and Korean have chosen to begin it on. The Kalachakra Tibetan New Year, for example, begins two new moons (plus one day) after the Chinese New Year, which is also the day some Hindus celebrate their lunar new year. The Hebrews begin their lunar year in September.
A digression: I fail to understand the A Simons Slam Dunk King 2021 Shirt of celebrating New Years in winter rather than in spring. Western calendar used to begin in March (i.e. in spring not winter). That is why September is called “Septem” – seven, not “Novem” – nine. New Year was changed to January to be closer to the supposed birthday of Christ. But why did Chinese and Koreans and Vietnamese and Mongolians celebrate their New Year at a time when the Northern part of Northern hemisphere is still reeling under winter? My guess is that it represents the hope of winter ending rather than the actuality of winter ending. Finally, I will end with one observation from my memory in India. Two linguistic states Telugu and Kannada of India celebrate the new year on the same day (i.e the two new moons after Chinese New year that I alluded above). When I was growing up, it was always called Telugu New year and I would get irritated. I later realized that it is sometimes natural for the bigger state to have more claims. So the Vietnamese and Koreans should not mind the “Chinese New Year” usage too much. “East Asian New Year” would perhaps be ideal, but for reasons mentioned above “Lunar New Year” would not.