Why only China has kung fu?

Kung fu is just a general term. For example, there are too many kinds of China, such as arhat boxing, shadowless feet and too many factions. Taekwondo in Korea; Judo in Japan; Thai muay Thai; Western boxing, etc. Just because Bruce Lee let the west know about China's martial arts, of course, there are also his various integrations, but because he is a native of China, China Kung Fu has become synonymous with China's martial arts ... In short, he is just a general term, perhaps because there are too many kinds of martial arts in our country ... As for why our martial arts have such a long history and are more mature than other countries, it should be related to the early establishment of feudal society and more wars.