Nothing you say changes the fact that the drop rate of shitty items is too high, and people have been saying this since day 1 the game was out.
Also GGG said they will never make an in-game editor for the filters because it's too much work, so once again someone had to do it for them.
As for chancing uniques, don't tell me that farming for one particular item drop is faster than just going through all vendors.
There is also the problem with how the game determins if a mob dropped something, and what rarity it was.
I believe it works this way: When you kill a mob, the game rolls if it dropped something. The chance for drop on a normal mob is somewhere around 16% according to the wiki. And only if anything was dropped, the game rolls for the rarity of the item. If you then cut the drop rate of items from mobs for example from 16% to 1.6%, then you would automatically get 10 times less rare items and unique items, which is not something you would probably want. The problem is only with white "useless" items.
So you would have to introduce some other change. Maybe something like roll if item dropped, then roll for rarity, and then if the rarity is lower than magic/rare, roll again if the white item is dropped at all, with a lowered chance. That should, in theory lead to the same number of magic/rare/unique items and less white items.
But then you have the already mentioned chrome recipie that would get significantly nerfed if the number of white items dropping was lowered.
The problem with going through vendors is that you have a limited number of vendors, one in each act, times 3 for difficulties, so at most 12 vendors that may or may not have the base item you want. And you cant restock their inventory for 24h, or until you level up, which is rare after level 90.
On the other hand, you can drop 12 leather belts in like 2 maps. And believe me, you will want way more leather belts to chance that headhunter.
The problem of too many items is most visible in maps, where you get increased item quantity, sometimes with 100+ value, and maybe increased pack size, or magic monsters, and you end up with screens full of items.
And you dont want to lower the Increased Item quantity, as it influences stuff like currency drops.
The solution GGG could do was either somehow decrease the number of white/blue items dropping, or create a way to hide them if a player do not want to see them. They decided to go with the hidding option.
And we didnt even mentioned the things like flasks, that drop only white/blue/Unique, so if you lowered the chance to drop of white/blue items, then you would kinda be starved for flasks, and keeping your flasks up to date is important. You could also introduce an exception. And some other exception for maps, and crafting bases over level 80, but then you would get close to what a lootfilter does, with the difference that a lootfilter hides items, and this would simply never drop those items. And out of the two, I like still having the items on the ground and not seeing them more than not having them at all.
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