I don't follow PoE but from what I understand the main issue was botting being rampant so they punished the non-botters by gutting the drop rate. Basically conceding to the botters "you win" and sticking it to legit players. Again this is another reason I'm so against any form of open trading. There may even be a good chance I'd leave the clan if they offered in-clan trading because we have so many botters as well. Bots today are far more advanced than they were back in D2. They can do more and perform more complex tasks than simply running Pindle over and over. So even if they guard themselves from doing runs like that the botters would just catch up by using more advanced scripts to do things.
I wouldn't exactlyhateadding some form of TC to D3. Like make it so Butcher has an increased chance to drop boots, Belial for chests, ZK for Bracers and so on. It would make focused grinding a bit easier. It could be an overall good quality of life enhancement. But I would only like to see that if trading is kept to a minimum.
And unless I completely misunderstood what you posted it sounds like if Blizzard let you make BlizzardBucks with real money but offered no way of transferring your BlizzardBucks back into real money is where the issue would arise. Since the RMAH was driven by BlizzardBucks and they already had a workflow to get BlizzardBucks back into real life currency I don't see how it's an issue. It also read more like it was directed towards more BitCoin operations. I don't know if Blizzard housing your BlizzardBucks would make them a money service. Either way they still support BlizzardBucks currency to buy games so wouldn't they be under the same guidelines and stipulations with or without the RMAH?