None of this half-assed "we're all wearing flak jackets but we fight with swords" business.

Is this a dunk on Fiennes' Macbeth specifically, or a reoccurring issue?

I think there's also a sweet spot in terms of, e.g., modern vs. traditional weapons in modern-set Shakespeare plays— as you said, having the conspirators shoot Caesar from a safe distance rather than stab him doesn't pack quite the same punch.