Is the traditional method of making katanas better than using modern steel? Here’s the answer from modern expert sword maker Walter Sorrels.
To summarize, katana blades made from modern steel have superior performance. They are harder and keep a sharper edge. They are also cheaper. The primary advantage of the traditional technique is that the folding process allows you to use lower-quality steel. Historical Japanese bladesmiths used the folding method because it was the only way they could make a good blade with the low-quality steel that was available to them. The other advantage is that the folding process makes an interesting and beautiful blade.