Of course they can.... why does this not surprise me. XD
I think what is most surprising is that they’ve actually done it, in practice. I would guess that they could have used any other component, as long as they can filter useful information from of all the noise. I would not be surprised if somebody else came up with a malicious firmware that activates the DVD drive laser and extracts audio signals by measuring the tiny displacements of the laser light in response to vibrations :D
This reminds me of the guy on google youtube that showed how you can harvest sound out of the frequency that LED lights put out.
Got a link?