As a rule of thumb, if an item has an actual use it will most likely show up when you press the key to highlight lootable objects (I think the default keybind for this is Alt)
Some random miscellaneous items will still show up when you do this, but at least you won't have to concern yourself with picking up random decor items such as plates and forks.
It's easy to get carried away and just pick up every item you come across, but after some time I learned to just mentally block out all the loot able items that were unlikely to be used for anything but decoration. I feel it does add some liveliness to the room though, at least when compared to other games' generic static backgrounds that you can't interact with.
That being said I do wish the game would tell you if a container such as a crate was empty before you opened it.
