Well, it's worked like a charm in the US with gun control, so why not knives?

THIS WILL END WELL: Germany Vows ‘Knife Control’ After ISIS Refugee Slashes Throats at Diversity Festival.

After laying a white rose at the site of the Diversity Festival slashing that left three dead and eight wounded, Chancellor Olaf Scholz promised rapid action would be taken against knives.
Right now, people in Germany can carry knives up to 4.7 inches long. The law will be modified so that they can only carry knives up to 2.4 inches long. No one appears to have considered the possibility that Muslim terrorists on the way to killing as many infidels as possible might violate the law and carry a concealed knife of 4 inches or longer. Such thoughts are unthinkable.*
There were 13,844 “knife crime” incidents in Germany in 2023, which the authorities are blaming on the existence of knives and not the perpetrators, who are reportedly mostly young Muslim men.
But locating the source of the problem is probably “not a very helpful insight,” In the UK, people sharing such insights are being locked up even as Islamic terrorists are being freed.

“Knife control” headlines were rampant in the UK circa 2018. The policy worked about as well you’d expect: Britain’s Knife Control Is A Bad, Real-Life Parody Of Gun Control.

* A tacit reminder that integration of Muslim immigrants in German society may not be going very well:

FWIW: A fact that America’s gun control zealots and the flying monkeys of the press rarely mention is the race of these murderers: black gangbangers. It’s pretty safe bet that almost all of them have criminal records that would bar them, under both state and federal laws, from even possessing a gun, let alone shooting it at someone. Many states have mandatory-minimum sentences for illegal possession of a firearm — none of them enforce it, because that would be racist.

The anti-gun organization Everytown has some interesting statistics on gun violence and the people and the places where it flourishes: