““Go on then, sell it to me. Why should I do Tai Chi?”
Why should I do Tai Chi If you have to ask in those terms, you probably shouldn’t do it. Your mind is clearly not open to the gentleness of the approach. It is not in the nature of Tai Chi that it can be “sold” like double glazing or life insurance.
It will draw you softly to itself as and when you are ready and you will hardly notice that you have been drawn in. There is no coercion, no discipline (except your own self-discipline), no tests, no “incentives”, no threats or 2 for 1 offer.
The approach to learning, like the movements themselves, can become a way of thinking, an approach to life. Tai Chi offers a way of looking at aspects of the way you behave and a mechanism for change if you want to use it in that way. It is as superficial or as profound as you wish so you should not really think Why should I do Tai Chi?.
Do Tai Chi because some aspect of it attracts you because it’s fun because you enjoy the company because it feels good because you just want to.
If you need someone to “sell” it to you, you are missing the point entirely. In that case, you might be better doing something else for now. It has survived for hundreds of years. It will still be there, waiting for you when you are ready.