How I see it, stabbing someone is far more illegal than carrying a knife, so if someone is open to stabbing a person, this law won't stop them from concealed carrying. Now what is more dangerous, someone having a knife and you can see it, or someone having a knife and you can't see it?
There are also usually separate laws in place that prohibit brandishing a weapon, so I think apprehending potential attackers isn't a huge problem.
I guess it might reduce the amount of knives involved in random confrontations as you mentioned.
Looking up the stats, the laws weren't effective in decreasing knife crime, in fact it rose by over 50% in England and Wales between 2014 and 2019.
But then again, apparently carrying small pocket knives under 7cm is allowed, and you probably don't have any legitimate reason for carrying anything larger than that.
There are legitimate uses for a knife besides using it as a weapon, for example slicing bread for a sandwich, opening packaging, slicing fruit etc., stuff that I could see myself doing at a beach...
My point was that even if you ban knives, that won't prevent people from carrying them, and this is confirmed by the fact that knife crime has been rising in the UK since the regulations have been put in place.
Tbf I thought it was a complete ban on knives in public, but apparently small pocket knives under 7cm are allowed, and you probably don't have any legitimate reason to carry anything larger than that, so I don't think the law is harmful, but it fails to address the core of the problem. And yeah, carrying a steak knife "for protection" is pretty strange...