I think it can be patched onto the Grid/Matrix systems without redoing the whole thing first. Just make terminals, QuickTerms and maybe a few new devices be the only ways to get the data out without surgery. The rest of the Grid/Matrix update or redo can be built around it. Yeah? That way you automatically accomplish this being an easier thing for corps and bosses flush with cash, riskier on Red and so forth.
Also no one has mentioned the data harming or killing you, but I think that should be considered. Either because of a cheap install job or because the data is actually programmed to destroy itself. It could cause traumas or lesions in the brain that affect your stats/skills or outright explode, or even switch to emergency power while shutting down your heart and kidneys so you die and preserve the data as long as possible. Just spitballing here.