Then yes, this is already a thing. I'm not sure which structures do it, but items that are not near a player-built structure will disappear after an hour.

If they are within the radius of a workbench, then I believe they remain indefinitely. There may be other structures that keep items on the ground, but I'm not sure.

There is also a certain machine you can build that you can put any item into it and turn them into coal with a little help from the gods.