The problem with the not-so-modern org chart is that it presupposes that people generally hold one role, have one boss, and that both of those states are semi-permanent, at least in-so-far as the chart is worth printing and distributing.
And yet, since its mainstream adoption nearly 100 years ago, what has changed? Everything. Business is dramatically faster, more dynamic, and more complex. The simple hierarchy has been replaced with a functional matrix where each employee can expect to have several bosses at the same time.