I mean not officially having Moon Elves and Sun Elves is almost as bad as doing a Dragonlance game without the Qualinesti and the Silvanesti.
Yeah, that's a real bummer. After reading some of the Forgotten Realms novels, it's really hard for me to think of Sun and Moon Elves as appropriately being represented as the same.
Even if mechanically they were the same, and most non-elven npcs didn't make the distinction, among elves the sun/moon/wood/drow distinction is pretty culturally important. Calling a Sun elf a Moon elf is in-universe stated to be a good way to start a fight.
Another poster mentioned gold/shield dwarves. Another important distinction. Since Gold Dwarves hail from distant South-Eastern Faerun, and would have a very different perspective. "Where I'm from, drow ride horses and worship Loviatar". "Chosen of Mystra? I saw far more impressive wizards than you in Halruaa, Gale"