Mark, when bureaucratic red tape makes it impossible or too burdensome to make the product, causing manufacturers to give up, then in my book that's the same as banning it, regardless of intention.
Of course CJD is a threat to public health, but there's no way to eliminate risk entirely. When you effectively ban gut strings when there's (a) no evidence of infected strings existing and (b) you'd have to eat several yards of those non-existent infected strings to get it, then IMHO the intention is to ban the product in order to protect people from a threat that doesn't even exist in the real world.