AH isn't the problem. Poe currency Trading is. If there is any way to trade items they will be sold for real money somewhere.

Reason I never play PoE for long is because I find poe items trading in any form boring. I don't want to check prices and figure how valuable my stuff is. I want to kill monsters.

I would love new Action RPG with no trading and all items only transferable between different characters of same account. Then adjust drop rates of items to not having ability to trade and maybe make some very expensive way to create exact item you want for build.

Most fun I had with D2 was when I found some nice item and started new build that was based on that item. Never had that feeling in PoE or Diablo III. Because of trading drop rates of any good items are so low that new player finding item they really want to use almost never happens.

Of course this is never going to happen in PoE. It is based 99% on trading so it would need total remake which won't happen.

Path of exilehas stated many times that they want things like haggling and flipping to be part of the trading system, because some players really enjoy those aspects of trading. Don't get me wrong - I'm absolutely not one of them, and in my ideal world we'd be able to set buyout prices that players could accept to insta-complete trades without us needing to log in and do anything, as long as they were willing to pay the exact buyout in the exact currencies specified. But that's where Path of exileis coming from, and the reason why we're rather unlikely to see any trade overhaul that includes a reduction in the amount of player interaction required to complete a trade.

If we could get offline/async trading through the website and an official clone of poe.trade integrated into the game client and/or the website, I would be reasonably satisfied. If Path of exilereverses course on the 'manual trading is fun' philosophy and gives us auto-buyouts, I'd be through the fucking moon and would play a lot more PoE.

And yeah, D3 AH was bad for reasons that wouldn't apply to a hypothetical PoE AH. Aside from the obvious rage over the real money aspect, the big problem with the D3 AH for me was that, on launch, gear was so goddamn boring and linear. It was literally just a matter of comparing two stats for most people: DPS and defense, both of which were composite scores that accounted for all the various offensive and defensive mods, respectively. I never went to the AH looking for specific interesting items, or even for specific combinations of mods on a rare - I just looked for items with higher numbers for those two stats and grabbed the best deal I could find that was a reasonably big upgrade. I didn't care what items dropped, just how much gold I could get for them, and I didn't care what items I wore, just what those two numbers were for each piece of gear. It was literally a worse itemization system than most friggin' mobile games with loot that I've played. Even games like Call of Duty had more interesting 'gear' systems than a game which is supposed to be all about the gear. Itemization was so spectacularly terrible in D3 at launch that I think it's dangerous to try and draw any lessons from the D3 AH and apply them to games where itemization is not spectacularly terrible.

Well, it can be done better and is not that difficult to do, but that does not mean it doesn't require time. For instance poe.trade adds an unnecessary layer of intermediation which adds a vulnerability to attacks like the one is suffering when you could just tap directly into the trade API and do a client-side only application.

Probably someone is exploiting the fact right now and preparing to rig the market BIG time. This is what happens when you suffer from over-centralization, with no redundancy: a poor non-resiliant system.

Anyway, but because it can be done it does not mean it will get done... Give it enough time of poe.trade being down and someone may actually bother to improve upon it and give anew alternative. But because somethign is 'easy' to do does not mean it does not require 'work' to do. And work for free comes at a cost of someone personal time, usually.

Why would I do it when:

I already maintain and contribute other open source projects which occupe my time

I don't see a realistic way of this giving me revenue, and is a maintenance nightmare

I don't even want to because I think Path of exileshould stop abusing the player base good will for their own good and profit and taking charge of this directly, as it's their business.

In any case, if they retake control of the system (as they should) and shut down external API, there are many ways of implementing trading systems than takes them closer to their vision of how trading should be and don't require a centralised AH with buyouts (if that's what they want to avoid). But it would require making some compromises and working around potentially increasing P2W (with premium tabs or similar) or taking the PR hit.

Auction Houses dictate that you don't actually have to haggle, it's who ever pays more or the b/o gets it in the time it's up the seller has very little interaction in deciding the price unless a reserve is put in and very, very, very few games have that. In an AH you are consistently up against everyone else trying to buy that item. [In PoE when you are selling a Disfavor you don't have someone going "11ex!!" then a pm 15 seconds later "11.5!!" "12!" etc etc etc. However in an AH that's exactly how it is, however it's digitized in the form of "offer:" as a button and "buy out" as another option.
Infact the only time I've ever seen that scenario is when selling HH and even then it's barely an auction [But XYZ certainly doesn't facilitate it as such]
XYZ is a lot closer to a market than an auction house.
I say Market because there isn't 12 people lining up to buy one orange, but there are multiple people wanting to buy a few oranges. Different vendors in the market are going to have different prices, some are willing to haggle, some are already at the rock bottom of their acceptable prices. PoE is a lot more like that with how XYZ is than pertaining to an AH in any shape or form.
I'm not sure how you could see it as an AH Mors, if the only pre-requisite to be an AH is that you list items for sale then by that definition any store ever is an auction house.

There is a lot of problems with current trading site compared to auction house. First how fast it updates, you pm someone for an item, which is already sold, they often don't even reply. Then there are people who simply went afk/alt tabbed the game - again no reply. Third group being people who decide not to sell item they set for sale with buyout price, for whatever reason, they figured they listed too cheap, because they got many offers fast. And all player interaction comes down to copy-pasting trade msg into chat, and either guy replying to you or not. How on earth is that better than normal auction houuse system with buy button, and item being transfered to your stash automatically without dealing with afk people all the time.
Oh I forgot one type of interaction, people trying to lowball you offering half the market price of an item, hoping you will sell. Thats about the only pms you get, other than copied b/o offers from website.