Taijiquan is really good for fighting and self defense, but yes it is hard to learn, it takes some time and hard practice. Like other old arts that have become popular, it gets spread around at less than its full potential and many things are lost in the popularization process. However, there are pockets of very good stuff out there.
To make such assumptions about the art is fairly common and understandable, nevertheless simply reflects a common ignorance due to the rarity of the real art. Taijiquan iis a real fightiing art, but you kind of have to actuallly go out there and find something good to really understand that. This finding process can however be very difficult.
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