Intentionality of the path is a good prerequisite of the object being technological, and its hostility is a possibility given the Dark Forest resolution is true (which we can't prove nor disprove). The sentence sounds a bit sensationalist but it seems scientifically valid to me, considering this is an area where we have little more than a bunch of unprovable hypotheses.
It isn't a good resolution, because it assumes all intelligent species in the universe must think and act according to the same rationale. But the one example of an intelligent species we're aware of (humanity) doesn't think and act this way - we've been blindly sending signals and probes out for decades now, and anyone observing our planet would probably notice obvious tech signatures.
