We used to feed only dry and it ended up causing us problems when we had to switch to wet for medical reasons (one had diabetes, and then the other ended up with CKD). The one who was supposed to be smart was somehow bad at eating it (she kept trying to chew it and it would fall out of her mouth 🙄) and also just generally didn’t like it because it’s not what she spent her life eating.
I don’t think dry food is inherently bad or anything, but if that’s your primary source of calories, then you do need to make sure your cat stays hydrated and also that they don’t end up in carb-overload (unless you didn’t mind the thought of giving your cat insulin twice a day, exactly twelve hours apart).
And it sounds like you don’t have to worry about this last part, but for anyone else reading this: please make sure your cats have some amount of both when they’re young and not so set in their ways… don’t make the mistake we did!