Flat is bad
In 2014, Jakob Nielsen confessed: “I really do hate it [flat design]. It’s this hot, strong word, but it’s almost true. I do think that it embodies some of the worst aspects of design, which is fads and fashion and disregarding the user’s needs”. I really don’t understand why NN/g tries to “conciliate” flat idiocy instead of declaring exterminatory war against it.
Useful collection of scientific articles about flat design: FlatIsBad.com