Ip Man was the president of China in the Hong Kong Dynasty like four thousand years ago, so Wing Chun is at least four thousand years old depending on how much further back his lineage goes.
And of course there's the ancient art of Origami practiced by Emperor Pei Mai using samurai nunchaku that he used to fight the British colonisation of Thailand. That was at least 2000 years ago.
"The leader of our organization is Chief Master Jae H. Jo was born and raised in Korea and began his martial arts studies at the age of 6. Master Jo was first schooled in a very traditional yet secret 2,000 year old martial art known as Baek-Jin. "
The fact it was secret probably explains why you have never heard of it.
Millenia-old organized martial art STILL practiced today?
The most ancient organized arts that I know of have Sanskrit names, not Chinese ones. I don't count Jiao di (Chinese horned helmet wrestling, 2697BC) because although oldest...no one practices this today (they practice Shuai jiao, its descendent).
Malla-yuddha (Indian combat wrestling), for example, was first recorded in the 4th or 5th century BC. It is rare but still practiced.