>>723744405
Same reason Elves have been downgraded from basically DemiGods to what we see of them in fantasy now. Because DnD needed things to be "balanced."

So an Elf with 200 years of combat experience is just as strong as a lv1 Warrior. So now Elves are always caricaturised as arrogant, but without any feats to actually back that up. Meanwhile, in LotR Legolas could do shit that nobody else could and it was just normal.