Dynamic audio power limiting introduces a whole host of audio distortions that would cause your computer to lie to you by not playing what you told it to. Your computer lying to you is a problem in principal I think, but specifically if you're doing any kind of sound editing/composition it's a huge problem because now you can't know if what you're hearing represents what you're creating or if your os or sound card has messed with it somehow.
As I mentioned, Dell could turn down the input volume to their amp/speakers. It doesn't totally eliminate the ability for a user to damage their speakers but it also doesn't create any distortions. I would guess that's what their bios update does. It just makes everything quieter for everyone.
I appreciate the principal that userland code shouldn't be able to damage hardware, but I'd much prefer my computer not lie to me. Now, I'm also not opposed to dynamic power limiters in general. In fact, that's exactly what VLC should be using if they insist on letting users crank things past levels that would otherwise clip. It just doesn't belong in the os or hardware.
