Why you couldn't switch over and use the non-free blob for the gfx card?
* Ethically: because you want to control your computer and not be controlled
by the developers of the non-free blob;
* Technically: nothing. nobody works to prevent you from installing
proprietary software (this may look obvious but consider the number of
people, in the proprietary world, who work on DRMs, Tivoization, etc.)... but
Trisquel does not help you to do so either (and you should not expect help on
this forum). For example, a non-free blob is not in the repository and will
probably break after each kernel update (even small ones). As a consequence,
I do not see a reason not to install the current version of Trisquel.
