I am not a sound engineer, but here's my impression of the issue. The maximum volume in the hardware is presumably set against typically expected waveforms. For instance, normally, if you watch a movie, there is no sustained high level sound. When there is no sound at all, the speaker coils and amp can cool off; during speech the background music is quiet or nonexistent and the pauses between words and variations in loudness will allow for further cooling; and so on.
The waveform compression in the volume boost reduces the differences between quieter and louder sounds, and thereby decreases the opportunities for cooling. This is going to be particularly true in the case of sustained playback of music.
If one sets the maximum volume in the hardware or firmware so that the speakers can survive sustained compressed sound, then the result will be that the speakers will be terrible for hearing speech in movies and radio. Granted, this could be fixed with higher quality speakers and better heat sinks, but that would increase cost and the audio system may need to be physically larger, while people like their laptops small and thin.
I guess temperature sensors in the speakers and the amp might help, and/or smart firmware that not only controls the maximum output but reduces output when high volume is sustained.
Another solution is honesty and user education: just explain to users that built-in speakers can be worn out with sustained compressed audio, and leave it to the users to decide how to balance audibility with risks to hardware.
(Like I said, I am not an engineer, but I do make a sound boost open source app for Android, which works by using the equalizer API to do presumably the same thing that VLC does. I put very obvious warnings about possibilities of damage to hearing and hardware in the app, but nonetheless the app was useful for movies and audio books. But using it for sustained loud music would be a bad idea. As of 4.2.1, Google patched the OS not to allow boost sound above default maxima. This protects speakers but is paternalistic and makes movies nearly unwatchable on some devices, I expect. Tradeoffs...)