That argument is actually on strong footing in principle, because only one counterexample is required to demonstrate that something isn't universally true a priori.
On the other hand, your argument is weak because 1) you attack a strawman (the commenter did not indicate by their choice of example that it is the most recent), and 2) you did not substantiate why developing military technology then would be different to developing military technology now, in such a way that precludes beneficial use.
On the other hand, your argument is weak because 1) you attack a strawman (the commenter did not indicate by their choice of example that it is the most recent), and 2) you did not substantiate why developing military technology then would be different to developing military technology now, in such a way that precludes beneficial use.