I suppose you could write a book complaining about airports, and those of us who fly from Dublin regularly would rate it very high in the complaints department. In its defence, I have to say I've been through far worse airports, but it could certainly be a lot better.
If you want to experience a truly awful airport my suggestion is to take a flight to Delhi. We in Ireland have absolutely no concept of dealing with 'huge crowds', but the Indians can do these like no-one else (apart from the Chinese). Delhi airport is a truly heaving mass of humans all struggling to get through the chaos to which poor planning and the Indian army subject its users. Even at 1am in the morning we were subjected to an hour and a half queuing to get through passport control, only to discover that there is just one duty free shop in the airport, and it is before you get to passport control. There is absolutely nothing on the other side, you're lucky to have access to a toilet (and a pretty stomach churning one at that).
It's enough to make you feel that Dublin airport isn't so bad after all, and that takes some doing.