It may be the most popular and balanced map in the game, but Valve’s decision to cull Dust II from the Active Duty map pool makes a lot of sense in the proper context.
Dust II has become the face of Counter-Strike as a whole. It’s rise to grandeur is no small feat and it is clear to see why it has gained its popularity. In the midst of huge debates within the community about certain maps (and in some people’s opinions the entire game) being favourably CT sided, Dust II existed as a shining example of how a map can be relatively balanced and not favour a particular side. There are a few whispering voices that may argue that Dust II is T sided but if this is even the case, it is to a very minor extent.
For historical context, Dust II was born after the inception of the original Dust map (also a defuse map) in the original version of Counter-Strike. Both Dust II and its predecessor were created by David Johnston (who also created Cobblestone). The original version of Dust was based on a map from Team Fortress: Brotherhood of Arms (a cancelled sequel to the original Team Fortress prior to Team Fortress 2’s release), and soon became phenomenally popular.
The original version of Dust had many balance issues however, prompting Johnston to create another version of the map. Fast forward 16 years and Dust II has long outlived its predecessor, and rightly so. However, in professional play this seemingly perfect balance hasn’t made for particularly interesting or exciting games (at least in my opinion).
When it comes to “memorable” games on Dust II, many appear to be upset victories. One that springs to mind is Team Liquid’s victory against Fnatic in the BO1 group stage game at MLG Columbus, where Eric “adreN” Hoag (previous member of the team) exceeded all expectations and had the game of his life.
But realistically, when you compare Dust II to other maps in the map pool, it generally requires less strategy and intricacy. And when many pro players were asked what map they wanted the Nuke remake to replace (prior to it replacing Inferno), most said that they hoped Dust II would be replaced.
The majority of the community would gladly argue that many of the best professional games have taken place on Inferno. Meanwhile on Dust II, CTs risk getting killed whilst simply going to the B bomb site at the start of the round.
It is currently being debated which teams have been most affected by Dust II’s departure from the Active Duty map pool, though this happens whenever any map is removed. Considering map rotations tend to happen only once per year, it makes sense that some teams will be affected by change after becoming comfortable on the previous map pool. So whilst Dust II is the most balanced map, Valve’s decision to remove it and replace it with Inferno makes a lot of sense from a competitive stand point.