YEah this took me like 3 leagues to figure out and still I was lost 1/2 the time a piece of loot dropped. I remember one league listing some dagger I found for a few C and I got like a million spams to buy it. Then one of the dudes that wanted to buy it told me the dagger was wort like a couple ex. Thats my experience with loot and POE in a nutshell.
But from my short time with this game, granted a while ago, the loot made more sense and crafting was way easier to get what you wanted, more deterministic?
Crafting from scratch in PoE is some of the most arcane bullshit in a game, you need several 3rd party sources to figure out what can be rolled in which slot, and in what order you should use meta crafts to block stuff from being rollable to get about what you want. It also was nerfed pretty heavily over time(lots of harvest nerfs and some baseline nerfs too). You're also still very RNG bound even in the "deterministic" ways of crafting, so you usually need to consider you'll have to reroll and rework your item several times in the process before you get what you want. And all the while, you need to trade for large quantities of materials via the godawful trade system.
Now slapping a specific mod on an existing item to fill your resists or whatever? Takes a click and barely any ressources, it's simple and nice, but actually crafting something is horrible shit.
As for the loot making sense, I guess kinda, once you understand what you're looking for. A lot of items you can parse and find they're trash in less than a second just because they rolled a key prefix/suffix at a low tier which isn't easy to fix, or because they have full prefixes/suffixes and not enough of the good stuff. It certainly can be pretty fast, but you need a solid understanding of what people are looking for in each type of weapon(armor is a bit simpler as most people tend to look for life+resist+empty or good stat) and the general meta builds at the time(which don't necessarily require the same things, bows for explosive arrow or toxic rain or tornado shot requires very different stats).
There's a massive barrier of entry to accurately estimate the value of anything you drop that's not unique though and a lot of people either don't bother at all, or drop everything in like a 100c tab and move the items down in value the longer they don't sell so they don't have to think about it(even then you still need a decent grasp of what can have value at all, like which bases sell and what are the good mods and whatever, otherwise you have hundreds of items to move about constantly).
I'd say overall PoE itemization is likely a failure, but it does keep people engaged because the ceiling for power level is so fucking high and for a lot of casual players(the vast majority of players) just farming maps for currency then buying everything off the trade website works well enough. They could simplify it a lot and make it easier to find good items while still having the crazy items I'd think(like phasing out low tier mods as you progress in higher tier maps, so you don't get +15life items in red maps kind of thing) but that'd boost overall player power and they don't like doing that, that's one of the reasons they always mention when talking about the lack of AH.