Every single race in D&D is just a "stereotyped human".
Take a Human... change its body shape... select three or four things it REALLY likes over all others... and voila, you get any D&D race and/or sub-race. So if people don't like Gnomes, it's because they just don't like the body shape or the three or four things the gnome (or sub-race gnomes) focuses on.
If players like playing Dwarves, it's cause they enjoy playing the human qualities of "gruff", "a heavy drinker", and "naturally comfortable underground" (plus of course all the beneficial game mechanics that go with that). And if necessary, throw in a Scottish accent. Because that's what almost all Dwarves are like in D&D, and what most players end up playing.
Now there's absolutely no reason why a player couldn't play a Human with those qualities... but if you're going to, you might as well just play a Dwarf because those are what have been earmarked for Dwarves in D&D since the beginning. Likewise, you could play an "aloof, outdoorsy Human"... but at that point you might as well just play a Wood Elf since that's what almost all Wood Elves are presented as. And the player who plays "aloof and outdoorsy"... there will probably be little to no difference as to how it gets plays at the table whether the character is a Wood Elf or a Human. So the two different races might as well not even exist-- except for the game mechanics one gives over the other (and is really what the player cared about in the first place).
For my money... it doesn't matter in the least which races or sub-races are used or not used in D&D, or whether "monsters" can become PC options or not. Because at the end of the day... they will be played by all the D&D players as nothing more than human beings with just a couple specific quirks and a rubber mask.