Japhet can you give me examples of async professional real life or online sports?
Real time information and time pressure are critical components and part of competition.
Being able to think fast in critical situation under time pressure is completely different thing than having days to prepare for each move.
Also it's hard to limit all external factors (including but not limited to stress, cheating, environment, etc) for such a prolonged (often more than a month) periods of time. This puts the competitors on uneven base outside of their control. Even more considering accessibility and other special conditions. Having as equal as possible opportunity for everyone is very important part of competition.
There are other factors and reasons too (like competing vs collaboration), but just in a simple comparison of async vs real-time in competitive terms I can hardly see any advantages for async.
I am not saying async is not competitive at all. It's just another relatively big compromise and excuse.
Often an e-sport tournament taking place online (instead of physical location) is not taken seriously either. Just to give an example of another competitive compromise.
Now, in the TTA case, adding the 3/4 player games where a simple resignation effects the whole game, the luck factor and the complexity of points system for comparing different players... Well how many compromises are needed to stop calling it competitive?
Unless by competitive you mean each player subjectivly comparing himself against other players... Then sleeping can be competitive as well (I had the best dream last night!)