So what do you use?
It is not just about the steel, you have the geometry, edge angle as well as the balance point to consider, the belly on German chef knifes is just silly....
But I suppose ignorance in your case is bliss...
lol, says the person who had no clue about steel or rockwell.
the bolster hasn't got anything to do with what you have said. The geometry also has nothing to do with country of origin, there's European and German companies offering basically every grind, there's even companies offering Japanese style knifes. That's before we even get into your fallacy of Appeal to Improper Authority, he might be a 2 star chef, doesn't mean he knows anything about knifes other than what he likes and doesn't like.
if you want some idea, i'm currently reading
Metallurgy of Steel for Bladesmiths & Others who Heat Treat and Forge Steel
John D. Verhoeven Emeritus Professor Iowa State University
if you hadn't guessed by the op, i'm somewhat interested in knifes.
and what knife you actually use as a Misono UX10 is very much European, Swedish steel with a 70/30 geometry. and again 59/60 rockwell, so not even particularly hard. Also with a European style handle and front bolster. so all this about geometry and stuff makes ou look even more silly, its made in japan everything else about it is a traditional European style knife.