You've only really reorganized the explanation I gave originally. Perhaps you didn't like the term "cashing out."B) they are "cashing out" by closing a popular source of revenue; they only lose cash by doing this.
I'm sorry but all of these notions contain backward causality, an unsupported premise and/or wishful thinking.
Occam's razor suggests that Blizz is shutting down D3's AH's because they have too much negative impact on the actual gameplay just as they state.
If you have low interest and player expectations on new players with a current system the means to fix that problem would be to remove the contentious system. By removing the P2W component and returning to a unit purchasing method I used the term "cashing out" to show that they're done with a continuous micro-transaction income in favour of a 1 time payout method.
Cashing out being the appropriate term as it comes from gambling. One doesn't cash out when they've got "all the money" available. They cash out when they believe that they've won with a strong margin and continuing on would likely result in a net loss.
So, yes, they are closing a popular revenue stream (ie: cashing out that revenue stream) in hopes that it will allow them to drive up sales for their console market.
Edit: After further rereading your post I'm coming to the conclusion that you must not be referring to my posts :S As the initial 1,2,3 steps represent the opposite of what I wrote. Derp.