Hopefully that video will help you understand that Tai Chi Chuan isn’t only moving meditation, but can be a real Martial Art.
“The principles that Tai Chi uses for fighting are quite different from those of most other martial styles, which rely on muscular force. Tai Chi uses the soft to defend against the hard, and weakness to defeat strength. The more you practice, the better you will become, and this defensive capability will grow with age instead of weaken. However, because the martial theory of Tai Chi Chuan is much more profound than that of most other systems, it is much harder to learn and takes a longer time to approach a high level of martial capability.
Grand Master Yang, Jwing-Ming