Have you played PoE?
Yes, for years.
The most popular classes always drive demand in a way that outstrips supply.
That is because drops in PoE are completely random and extremely rare to find any given good item.
If good items are sufficiently rare in LE, this will also be the case. The most popular build will want some item and there won’t be enough entering the market to meet that demand. A good example might be…Starforge in PoE. When half the endgame population is playing Cyclone it’s worth 10+ exalts, when no one was playing Cyclone it was often 1 exalt or less, despite the rarity and accessibility staying the same (prior to Conquerors of the Atlas, which lowered supply significantly).
Fallacious comparison. PoE has random drops or, in the case of the Starforge example, extreme end game that less than 1% can even get to. There is no item like that in LE. Not only that, you are completely ignoring the Smart Loot systems impact on supply.
Smart loot systems specifically make loot for other classes rarer. If a particular class-specific item is worth a lot in a specific meta then you’re lowering your chances to find it if you’re not playing that class, lowering your income by some percentage based on that item’s drop chance as well as any other items like it that are similarly made rarer by your class choice.
Again, you have a fundamental misunderstanding of supply/demand and how the market is changed with a smart loot system. Smart loot systems lower demand for “meta” items as the meta players will find the items themselves more often. They find them more often because the number of non-meta drops are significantly lowered based on the smart loot filter. If anything, the meta in a smart loot game increases the cost of niche build rare items because nobody is looking for them. At least in PoE there is a flood of niche build items and that makes them dirt cheap.
By this same logic, anyone not playing the meta build is lowering their income anyway. Meta builds are thus for a reason. They are usually the most efficient at farming content.
Some people enjoy playing the game to min/max. Some people want to see their currency grow and their goal for a league or season is to make a certain amount. It’s just another axis of gameplay. As far as “what do you need currency for?”…what don’t you need currency for? If trade exists then the items you want or need can be bought and making a transaction via trade is significantly faster than making or finding an item yourself. You say it would take less time, but that’s just not true unless items are exceptionally common or crafting is too easy. The best items will be rare and hard to come by as a single player. But given a large number of players someone is likely to find one or make one and put it up for sale, making what would normally be effectively inaccessible accessible via trade. If you want a good example that is currently in-game in Last Epoch, look the Fractured Crown. A solo player is very unlikely to get one and to even attempt so is a massive undertaking in terms of time and items required. It’s an item that is likely to be primarily obtained via trade from people who get lucky and acquire one unintentionally.
Some people also want to cheat and steal and grief. Not every option is optimal for the growth of a game.
As an aside, if you think Gold will be the currency, you are fooling yourself. Gold is useless. This game will devolve into the same thing that D2 did with trade. Things will be priced in some semi-rare ubiquitious item (Like SoJ in D2). If there are items that have extreme rarity, which I somewhat doubt (I bet Crown gets removed.), then there will be a scummy real money black market. The ONLY reason that trade works in PoE is because of their currency system being tied to the crafting system.
Finding new items not meant for my class is also a great source of inspiration for creating new builds and am afraid that the reduced drop rate will hinder that.
