Well keep in mind destroyers versus coastal guns or Battleships have to get in close. They are badly outranged. Even in D-day a few destroyers got in really close for bombardment. If you think of it that way destroyers as melee is a lot less annoying.
Japanese destoyers tore the Us navy apart in Guadacanal with torpedo assaults which required you to be pretty close just think of it like that. Oh and they need to depth charge subs which requires being really close. Ca't hep you against early eras but thats part of civ. Was always annoying in 4 when my cav got riiped to pieces by longbows.
I was talking with my friend about this the other day and we agree. I think when people see the destroyer unit in game they think of modern missle destroyers (which to my knowledge are almost completely phased out by now) and they think it should be long range. But I picture they as WWII era DDs, they have to get in pretty damn close all things considred. The missle cruiser (which, again to my admitedly limited knowledge, is what replaced missle destroyers) is what people envision with the in game destroyer, even though we have the missle cruiser for that role. Although it does come rather late.