here is the thing though.
Karmas jobs is to create a shield and to harrass, but if a champion who is similar to her out classes her in every way, than this makes her a "bad champion" for now you are comparing a pistol to a gattling gun. (if we are talking pure destructive force) The whole point of riot creating simmiliar champiosn to one another is so people who have that play style are given options. "do i want karmas ability to assist her entire team with ult shields, and her superior power to deliver the heavy hits, or do I want lulus ability to cc people and peel for her adc? Or do I perhaps want jannas major disengage ultimate?" It was suppose to be like a toolbox, but with karmas shield nerfs, it simply caused a chain of effects where she just became greatly out classed.