Complexity isn't much of a concern since all dependencies should (ideally) me automatically managed by NPM.
The greater benefit is reduced duplication and reducing excessive folder nesting. The former saves space and the time required to download dependencies, the latter solves some serious issues with using NPM on windows.
Yes, I noticed that when I upgraded; spent several hours debugging before I found out that was the problem (I had both flat and nested, where prod used the old, and my tests used the new)
Complexity isn't much of a concern since all dependencies should (ideally) me automatically managed by NPM.
The greater benefit is reduced duplication and reducing excessive folder nesting. The former saves space and the time required to download dependencies, the latter solves some serious issues with using NPM on windows.