The PRC lobbied to have tjq included on UNESCO's list of Intangible Cultural Heritage/s.
An intangible cultural heritage is a practice, representation, expression, knowledge, or skill considered by Unesco to be part of a place's cultural heritage.
The history of the practice is not really critical. It's the importance of something to "a place's cultural heritage." No matter who invented tjq, the Chen variety has not been the most influential to Chinese culture. The addition of Taoist and other elements is what makes tjq tjq to the majority of people who practice the art. It's not Chen family or Yang family style that defines the way tjq fits into China's "cultural" heritage as it is understood.
That's what distinguishes it from bagua or xingyi. Why aren't they on the list? For whatever reason, tjq (specifically via the cultural concept of taiji) has become the most important representative of Chinese culture in the martial arts. It ain't because it's superior to any other. Shuaijiao is at least as effective (:)) and much older. But, it's not culturally unique --probably because it hasn't been linked to any ancient Chinese philosophy.
Without the "woo woo" stuff, the medicinal qigong claims, and the interference from philosophers and scholars, tjq (or Chen family style CMA) wouldn't be anything special culturally. Buddhism was invented by the followers of Buddha, but that's not what makes it culturally important. Then again, the debate about origins is also something that makes tjq what it is. Anyway, who wants to take credit for tjq's success as a martial art today?