I find elven lore fascinating, although I don’t like the origin story of them sprouting from Corellon’s blood. But that’s just me.

EDIT: Actually I kinda do like the bare bones of that story, but I imagine the battle between Corellon and Gruumsh taking place in the Feywild, so that the Feywild (where Corellon’s blood is spilled) becomes the primal home realm for all elves and the different sub races spread out from there.

Quote from Nechaef >>

Quote from Shepherd_Hubbard >>

From the link: Grey elves were a sub-race of high elves endemic to the planet of Oerth and Greyspace.

Take it up with them if you disagree.  Yes, it speaks of their isolationism, I'm uncertain about lifespan, but I'l ltake your word for it - and from the other link: They were considered high elves sometimes also called eladrin.

somewhere in those two links, it speaks of travelers from oerth to Faerun sometimes mistaking moon elves for Grey elves due to their similar appearance, and it talks about grey elf cultural similarities to the Sylvanesti of Kryn and the Sun Elves of Toril.  

edit - found it it; at the bottom under trivia: 

• Visitors to Toril that were familiar with this race of elves sometimes suffered from confusion, due to the fact that the planet's silver elves, whom they a bore a resemblance to, were also sometimes referred to as gray elves. Though this term was considered by them to be a pejorative.

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I don't make this stuff up.

 https://greyhawkonline.com/greyhawkwiki/Elf use the correct lore aggregator then? Toril is Toril, Oerth is Oerth.

 Also Elves of Greyhawk stand about a foot shorter then Elves of the Forgotten Realms, the only elves as tall as the realms elves were the Valley Elves which lived in the Valley of the Mage and were the least populated race of elves.