there is no reason, or at least they are not prepared to give one, they just keep saying it will be supported in a future version.
if you go into the release notes inside of the asiair pro app and look at version 1.0.9 it clearly states that the 2000d IS supported and it was this false information that led me to buy the asiair pro and the 2000d.
i have been waiting months for eos 2000d to be supported and ended up buying another camera just so i could actually use the asiair pro as i was unable to return it for refund.
i still have the 2000d and would still like to use it with asipro, but from stating in ver 1.0.9 that it is supported to now ver 1.5.1 and still no support and still no reason why or when i have lost faith in ZWO as this post is over 1 year old!!
The products are amazing but the disinformation on many products and the lazyness of the support tech in this forum is far too much for me to buy ZWO again.