Ok, sure!!
This whole idea, that the game needed less capitals, is outright stupid. It effectively always had only the current expansion capital, and Stormwind/Orgrimmar outside of RP servers and specific quests. There is no real reason to bind your hearth to Undercity, Thunderbluff, Darnassus or Ironforge, let alone the BC-era capitals. All players were already funnelled to at most two cities.
And “destroying” Undercity and Darnassus didn’t even “get rid of” any capitals; they’re just behind a phase now. Levelers still pass through them as needed. Capped characters still visit them as needed. Nothing is gone from a mechanics perspective or from a convenience perspective (because both were already lacking in conveniences compared to SW/Org).
There is no benefit to “getting rid of” these two cities, and it’s dumb-headed logic to think they “needed” to be gotten rid of.