Can't speak as a fighter, but as an observer, especially for westerners, training & fighting is a self-disciplining act. You are putting yourself through something, and when that manifests itself as something like low-body fat, and exposed muscularity, it makes sense that that is part of the meaningfulness of doing that. It also helps that big cutting is seen as a way of gaining advantage in matchups, so if you win that way, it makes sense for it to add to the meaningfulness of the training & cut.
But, you are right, it does detract from just becoming the best fighter you can be, developing the skillsets to win in fights closer to your walk around weight, etc.