That's an extreme form of simplification. Simplification is not performance optimization at all; it's removing non-essential complexity. You can still have abstraction and layers, monads and features. The thing is not to keep adding them when a refactor makes them redundant.

Like I say, our designs are ancient and lack features; we need to add more stuff to the code. But that will enable us to remove abstractions that were added only because our previous designs were crap.