If you don't know this already, you probably live under a rock - people are averse to change. Anything different is liable to get shot down, as we can clearly see in the CEVO Judging video that 3K made.
I think Valve isn't adding this map mostly just because the theme is different than you'd expect. It doesn't take place in a warehouse full of crates, like most maps - it tells a story. Telling a story through level design is hard, and this map does it just right, but CS:GO doesn't usually feature maps that do this. I think that's why Valve hasn't added this map. It's different. Not worse, not at all. Just different.