  Functionality is a graph complexity measure that extends a variety of
parameters, such as vertex degree, degeneracy, clique-width, or twin-width. In
the present paper, we show that functionality is bounded for box intersection
graphs in $\mathbb{R}^1$, i.e. for interval graphs, and unbounded for box
intersection graphs in $\mathbb{R}^3$. We also study a parameter known as
symmetric difference, which is intermediate between twin-width and
functionality, and show that this parameter is unbounded both for interval
graphs and for unit box intersection graphs in $\mathbb{R}^2$.
