Uh, hold on. That's not what's meant by intentionality. No one is talking about what a machine intends to do. In philosophy, and specifically philosophy of mind, "intentionality" is, briefly, "the power of minds and mental states to be about, to represent, or to stand for, things, properties and states of affairs" [0].
So the problem with this guy's definition of intentionality is, first, that it's a redefinition. If you're interested in whether a machine can possess intentionality, you won't find the answer in interpretivism, because that's no longer a meaningful question.
Intentionality presupposes telos, so if you assume a metaphysical position that rules out telos, such as materialism, then, by definition, you cannot have "aboutness", and therefore, no intentionality of any sort.