By the way, "lithe race with unusual strength" is by no means a recent trope as far as D&D is concerned: on average (and more so in other settings), elves are both shorter and slimmer than humans and yet they do not suffer an inherent penalty to Strength.
They did in the older rules, though it was -2 Constitution, +2 Dexterity. Halflings and gnomes were on the -2 Strength side of things.
Nowadays implying that a fantasy race may have certain physical and mental predespositions based that contributed to their development as a species or are a result of divine/otherwordly influence and can be in certain ways inferior or superior to others is seen as a capital offense, though. Then again... why would humans be, on average, more intelligent than dwarves or halflings (racial +1 Intelligence) if the point was to erase inferiorities?
Going dangerously off-topic and touching a... touchy subject here, so I'd rather not delve any deeper.
