I don't like price histories much because they only encourage people's notions of what a price "should" be, when its completely irrelevant to what the price is. So many people are guilty of going up to an AH/vendor/store and feeling they should be the one to buy item X, and they should only have to pay Y. Anything above that is outrageous.
That's how free markets work. If the price listed is too high, nobody wants to buy. If people aren't buying, sellers don't make money. Sellers that make no money will lower their price.
Right, the important information isn't what the last 7 iron swords sold for, but what the X iron swords available for sale right now are. Market wards made a huge improvement when they started showing some of the prices, but they'll take a step backwards if/when they start showing price histories or attempting "regulation' or trying to stabilize prices.
It seems you have the popular position, but I'm of the feeling that more
information is what builds a fair economy, not less. Scams are born when people don't know they're getting ripped off.
FFXIAH was so popular because it offered even more information than what you could get in-game. I think increased information would keep prices more stable and more fair than less.
The concept of fair is subjective. If there is one copy of an item for sale, and the seller wants triple the cost of what it was when there were two, that's his conscious decision to make just as its everyone else's not to buy it. If nobody buys it, its his loss. It someone does, than the price was 'fair' to at least two people, which is all that matters.
I know a bunch of people just want the prices to remain somewhat stable, which is fine, and 99% of the time it seems that competition keeps that in check. Where I dislike it, (and feel that we shouldnt have a price history because compition is enough) are when there is one copy of an item selling for X when the price history says it was Y, and someone starts complaining about a scam or "price hike" when its actually just a reflection of scarcity.