I'm a bit puzzled by this. When I click on Tournaments I get a listing of "All Public Tournaments" which has all the open tournaments at the top (they usually don't even fill page 1). I wouldn't ever use any of the other formats unless I was looking for a particular private tournament. Even then, if I know the club or clan who owns it, I can go to their tournament page or home page and see what's available. I'm aware that there are a large number of inactive clubs and some offered tournaments go back several years, but that kind of housekeeping is pretty low on the programmer priority list because it's only visible if you're digging for it.
I'll agree that navigating around the site isn't user-friendly because of the lack of searching options, but there's usually a workaround somewhere once you figure it out.