Except they are not plausible at all.
Well I think that is where you are diverging most from other posters. Plausibility is up to you to accept or reject.
Any poster with a reasonable knowledge of physics and history could pick almost any game mechanic in D&D, deconstruct it, and show that it is "not plausible at all."
Want to pick a mechanic you think is a good counter-example to a hobbit getting +damage with weapon (i.e. one you like) and switch roles, with me arguing how it is implausible, and you arguing how it is in fact just fine, without resorting to gamist defence of your position?