It isn't that I object to the new races or the old ones per se. My objection is to jamming every single freakin' one of them into every single freakin' published setting. Adding new races to the list makes the problem worse, not better.
If elves suit the theme and atmosphere of a setting, then by all means give it elves. Ditto tieflings, dragonborn, warforged, and the mighty Armadillo People. (Okay, so I probably wouldn't want to run a long-term campaign in a setting where that last one was a natural fit.)
But there are many settings in which elves and dwarves have no particular place, like a gritty, bloody, swords-and-sorcery world inspired by the works of Howard or Moorcock. They are entirely superfluous there. You can reskin them Dark Sun-style to make them fit in better, but you're still shackled to the idea that every world simply must have something called a "dwarf," that bears at least some resemblance to the short, stocky, iron-forging, tunnel-digging, mead-swilling, Scots-accent-mangling stereotype of dwarfdom; and players must be able to play one.