(2.2.10) Draxl : Indeed, the bad reputation of the Kohn-Sham system may often come from the fact that we either tend to overinterpret results or are not precise enough about what we are doing. Sloppy phrases like "DFT is well known for its notorious band-gap problem" might have been considered appropriate long time ago, but should not be said anymore in 2021. Pointing out the self-interaction error (SIE) of many functionals is certainly important, but we should always make clear at the very same time that Kohn-Sham eigenvalues are not supposed to provide band gaps.