If Tyrande is coming back, further discussion regarding this is almost useless. But my thought on some of the questions you asked,
Yes, these promotions are about $, and I have no idea what legal issue is there with Twitch/Amazon and Blizz, but these were simply promotion deal, nothing special. I mentioned this before, but you act as of this promotion deal was Blizz trying to backstab or turn its back on its playerbase. It’s not. It was a normal promotion deal to boost up Twitch Prime subs, only Blizz never expected backlash/outcry to be this severe.
For instance, people who cried over Tyrande never bothered to complain about Twitch Prime only card backs, golden classic pack (before Blizz gave 1 for free to all players), etc. Why do you think that is? Even Khadgar, iOS only promotion deal (albeit you could bought it using one of your friend’s iphone) was much less complained about. I’d say these people already know what a normal promotion deal is, some simply exclusive, out of their reach, not everything is entitled to them. They only complained because it was a Tyrande skin.
Rational? Not really. But I’m glad they finally can have their peace now.