This just isn't true. A knife is far more concealable, far more stealthy in the aftermath of a shank and move (look at prison shankings going unnoticed all the time), and far more likely to cause death. China literally has a mass stabbing problem. Generally targeted at elementary age children. One specifically killing 33 and injuring 130. You're just falling for propaganda rhetoric.

In self defense knives increase the chance to injure or kill yourself over a gun or with just your hands, increase the fatality rate for any stabbed over being shot, and rarely lose against anything in close quarters (hence why you run from knives but try and redirect the barrel a gun when possible). Dirks and daggers are well known to be one of the most dangerous weapons created and were literally outlawed throughout history, in some places even currently.