>The Sindar AS A PEOPLE don't exist anymore.
Sure they do. Go look up the Appendix notes of the fighting in the War of the Last Alliance, and you have the Sindarin royal contingent described as being a very different fighting force than the Silvans that are along with them. And as you note, the two main "polities" of Silvans are ruled over by non-Silvans, with a Sindarin king of the Woodland Realm and whatever you want to call Lorien's government, since it's not clear whether the Noldorin Galadriel or the Sindarin Celeborn is in charge.
If you mean there aren't any Sindarin ethno-kingdoms around, sure, but you don't have that for any of the other Elven realms in Middle Earth either, given that there are all 4 of them left and they're all reasonably mixed by this point. So I really don't see what your point is.
>he Sindar on themselves learned craftmanship from the Noldor,
The dwarves originally, actually.
>, and the whole reason they were allowed to rule the Nandor was their superior knowledge and wisdom.
Their superior power and weaponmaking, which let them protect the Nandorin from the orcs.
Which, by the way, isn't the ancestry of the Sindarin rule east of the Misty Mountains. From Appendix B
>but before the building of the Barad-Dur many of the Sindar pressed eastward, and some established realms in the forests far away, where their people were mostly Silvan Elves. Thranduil, king in the north of Greenwood the Great, was one of these.
2nd age, not first.
>So no, they aren't primitive, much less the Galadhrim who are ruled by an actual Noldor queen
They quite literally and explicitly are described as such; it's their rulers, their non-silvan rulers, who do all the metal, stone, and magic work.
oocities.org/ulmo10/ut-cg-appendixb.html
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