Durability is an ineffective way to discourage bashing chests or doors open since there are far too many ways to render it meaningless (spells, throwaway weapons, fists, etc) and it adds an obnoxious amount of micromanagement to the overall game for the sake of one issue.

Breaking items in the chest is, if anything, even worse, since it imposes a "correct" way to play (Thou Shalt Take Lockpicking) and if someone wants to argue realism, the realistic way to open a chest or door would be to use a crowbar, or perhaps one of those pieces of scrap metal lying around everywhere, to lever it open rather than supposing that "wail on it with a greatsword" is the only possible method of forcing it open. For that matter, you could "realistically" just pick up a screwdriver - or a rock and nail - and dismantle the lock or hinges at no risk to the contents.

A lock doesn't keep people out by itself. It's just there to slow down/inconvenience someone who wants to get in, making it more likely that they'll get caught in the meantime. As it happens, all of the in-game options DO take time and most make noise, increasing the chance of discovery (especially with the new tracking system). Given that, durability/breakage is superfluous.