^^^ It's simply giving the event a more accurate name, Gromit.
Quote:
"The Lunar New Year is a public holiday that is observed across multiple days in China, North and South Korea, Malaysia, the Philippines, Indonesia, Singapore, Brunei, and Vietnam. Filial ties typically take center stage during this time as people return to their hometowns to observe the holiday with their families."
Source:
https://time.com/6248736/lunar-new-year-celebrations/
Western nations, especially the UK, have tended to refer to 'Chinese New Year' simply because there are large populations of Hong Kong Chinese descent in several parts of those countries. So we see fireworks and street celebrations in, say, London's China Town. However we don't have many large populations here who've descended from families in, say, Vietnam. So we don't as readily link celebrations for the Lunar New Year to Vietnam as we do to China.