I did two orders from Aliexpress recently. On the first one they did count the fee per item, on the second they already had the categories figured out & counted the fee only per category.
Since then I am now getting "duty saving" adverts for them where they help you to get items on sale & in the same category. So it took them like two months not to only adapt, but to use the fee as apart of their marketing. ;-)
Oh ok I kinda stopped ordering from them since it was introduced. I've been ordering lots of stuff before it came in so I could have some stock of things I use a lot, like WS2812B LEDs, micro screws etc.
I was really infuriated when I heard that it was mainly the big chains like Lidl, Aldi, Ahold that have been lobbying for this crap. They are always trying to kill the little guy.