That was probably not GP's point, but they can be. Sound-based weapons are a thing: https://en.wikipedia.org/wiki/Long-range_acoustic_device

Of course a lot of it is about the energy and overall exposure, and the harms of this, if any, are more likely elsewhere, but it's completely reasonable to question extraordinary promises made by people who up to this point have shown no expertise in the field.

I swear, it's like some people have already forgotten about Theranos.