If there is an item kept somewhere: if you don't use it from there regularly, but it's visible, it's a decoration.
I am not ome who requires everything to be perfectly matching and designed; I value functionality, and practicality; pragmatism; using what you have, and thoughtfully designing with it.
But if you don't actually use it there often, but it's effectively on display tbere maybe just because "oh it fits in that spot" then that is functioning and impact the space merely as a decoration.
And if when you think of it as a decoration, it no longer makes sense for you to have it there, the space would probably be better then if you can find another place for it.