Let's just hope that the politicians never realize the danger of sharpened sticks or they might ban trees and bushes too.

Of course, I never intended to imply that a plastic knife would not be dangerous

maybe instead go to the wikipedia page for 'Gravity Knife'

or just read my comment more fully. Gravity knives don't have switches. or buttons. If you're considering the hinge mechanism that allows a gravity knife to operate, then practically any folder is a "switch blade" and that's just not true.

from the wiki I linked:

A gravity knife is a knife with a blade contained in its handle, which opens its blade through the force of gravity. This mechanism of opening is fundamentally different from the switchblade...

Even in gravity knives that appear to be opened by a switch or buttons... all that button is doing is unlocking the blade to allow it to be deployed or retracted. If simply having a button or switch or something is all it takes to be a switchblade, then this classic gem would also be a switchblade.

So, I'm going to preface this with a quick reminder that once deployed, a folding knife is going to cause the same kind of wounds as a fixed bladed of similar size and shape. and example for this is the Benchmade Adamas family. They have a folding knife, an auto-opening folding knife and a paracord wrapped skeleton-grip (with paracord,) fixed bladed knife.

Once deployed, the knives are all going to do about the same in a fight. And the two folding knives- the auto, and the manual knife- are going to function basically identically. In Minnesota, the only one of these that's illegal to carry is the auto. The only reason that's illegal to carry is because of perception. (the same perception as switchblades.) There's no practical reason that auto-opening knives are any more likely to be used in some kind of crime than manual-opening folders.

Back in the early fifties, switchblades were frequently used by youth gangs (west side story, for example,) or rough-and-tumble types (especially in cowboy or war movies,) as a sort of visual code to indicate they were of rather dubious character. eventually that became associated with black guys being villains, because hollywood never met a trope it didn't like. even when the villain was white, or whatever, that was broadly overlooked by popular culture.

It was outlawed in '58 largely because people perceived it at the weapon of choice by black men. it had nothing to do at all with knives themselves being particularly dangerous. or even all that common, really.

the same is true of asian martial arts movies and balisongs. (which is ridiculous. the only thing a bali should be used for is as a slightly more exciting fidgit spinner. Sorry.)

Or brass knuckles (relating to the italian mafia and irish mob. hollywood gave those to the enforcers.)

This isn't to say that maybe knives and brass knuckles and things shouldn't be regulated. But outside of "Knives larger than x length", and the occasional feature like double edges or spear points (Which are bad for general use, and usually purely for a weapon, not a tool); there's always some other reason for it being outlawed.... and generally that reason is that "the wrong people" are using them.

Sorry, I formulated that badly. They used to be legal up until the 70s or 80s.