Who can find 20 dresses that tick the boxes? So elusive!
I can't really play the game because of that!
But, I think it's harder to get lots of different silhouettes that match body type (maybe more so for work, which could have more limitations on styles) , so often one might duplicate, either exact dress/different color, or very similar dress style.
Diana's point about summer wear and washing makes having multiples sensible, so maybe you're "splitting wears" in the narrow sense, but you need them to avoid laundry bottlenecks.
Using my dress-scarcity mentality and the French wardrobe mentality, I would be grateful for fewer, but very excellent-fitting/fabric dresses for work, more of the blank canvas type, and might do more with scarves or jewelry or shoes. Oh, drat, except it's hard to find comfortable workday shoes for dresses, so I might only have one or 2 pair in a dress-shoe capsule!
Also it's fun to find dresses that you can wear a sweater over, either a boxy pullover or a buttoned cardigan, and make it look like a skirt and top, for more versatility and for warmth.