I thought they looked bad as well (Louis, Harry,Zayn ). The only one who looked about the same was Liam.
Sure they are ageing as does everyone, But their styling (hair cuts & clothing) is what is really making them look so bad. I'm sure they are at a point where managers do not have much say over styling & maybe they are trying to figure themselves out or something?? But, they could easily have a fresh & more attractive appearance- with hair cuts and the right clothing choices.
Maybe they will soom grow tired of the phase they are in look-wise, and in several months emerge with a fresh update/ makeover.