Comparing dwarves with elves, dwarves will always be shorter, while elves don't need to sleep. This is why I never had a problem with attribute adjustments and think it is a shame they are gone. I liked that on the whole elves were more graceful, and dwarves more sturdy, that's flavour has gone, when there was nothing wrong with it in the first place.
No, the flavor can still be there... the book can still describe the typical dwarf and elf in that way. The
game however, doesn't need to attempt to portray this by using minor ability score bonuses. 1) Because it inspires/lightly forces players more often to make use of those bonuses and continually play classes for which those bonuses apply (leaving a bunch of class options off the table unless the player is okay with being less optimal than they otherwise could be) and 2) Because players can set their stats however they want... so often you WON'T have sturdy dwarves and lithe elves-- thus rendering the idea that these ability score bonuses accomplish something meaningful completely moot.
When people say they need elves to get a +2 DEX to illustrate how "graceful" they are... they are thinking about the elven species on the whole. They see +2 attributed to the race write-up and it allows them to visualize the idea that every single elf is somehow more graceful than everyone else. But that doesn't take into account that a whole bunch of other races also get a +2 DEX, meaning that elves aren't actually more graceful than anyone else, they are only equally as graceful as like a half-dozen other species in the game (including some variant
Humans who put their +2 into DEX). And it also doesn't take into account that just because they desire to see all elves as these lithe and graceful creatures... the +2 DEX only applies to Player Characters... and more often than not that elf in the party WON'T be more graceful than many of the other characters. In fact, you can easily have parties where the Dwarf has a higher DEX than the Elf does. Thus proving that ability score bonuses don't accomplish what they are trying to do. If the primary elf we see in the campaign week after week, session after session is a blundering fool compared to the dwarf, what did that +2 DEX functionally accomplish towards the description of "elves"? Nothing. So why bother having it as a
game option, when all it does is cut down on a number of other game options people will feel as though they are willing or able to play?
The
game of Dungeons & Dragons wants characters to have high primary stats. And that can run counter to what the
narrative of the campaign world might feel like it wants to get across. And when those two things are in disagreement... I believe (and I would say at this point WotC does too) that the
game takes precedence. Make the game more open to more players. And then let those who want to restrain their game's options do so... but do it on their own time at their own table. After all... you don't need the book to tell you that all Elves should put their +2 bonus into DEX... you can just tell your players you are instituting that rule yourself.