These are the very words I was seeking before my morning coffee truly settled in.
Like you say, there are narrative truths to each species that, I think, are more important to most players than the mechanical benefit. Being an elf means something, even if you don't get a +2 to Dex and proficiency in longswords.
The mechanical benefits help, of course, but I think one of the reasons a lot of discussions on species mechanics gets lost in the weeds is because for most players mechanics are a secondary incentive. The narrative truth is the primary incentive.