Yes, a Salvatorian Clause is normally necessary, but this law was specifically written saying that the clause in the contract just doesn’t apply. The rest of the contract stays valid.
The "Do not break DRM" on Computer Software is equally invalid. (Warning: the "Do not break DRM" on music and video is a criminal offense on the other hand).
DISCLAIMER: I am not a lawyer, this is not legal advice, if you consider to use this as defense in a court, you might want to consider getting an attorney. Details can matter depending on your jurisdiction.