When you go to fish markets and restaurants in Asia, they're not using expensive knives to cut and slice the fish. And they slice and serve up lot of fish. Way more than sushi chef at fancy restaurant. Same with when you go to the fruit market. But the blades are very sharp. None of the home cooks with their expensive knives are going to cut fish better than some of the workers at the fish market. Cheap knives are good enough. Expensive knives are not going to help majority of home cooks.
My response was to a comment that properly sharpened knives are a 'hobby'. Now, yes, those knives are very sharp. And you know what the people at fish market do every day? Sharpen their knife! You know that useless 'hobby'. The knife style for cutting up whole fish is completely different. They are made with a tougher steel with more steel behind the blade. In Japan, they use deba knives for carving fish and yanagiba knives for cutting fish for sushi. Many other countries use different clever designs.
A yanagiba would chip apart if used to break down a whole fish. Does that make it a bad knife and a deba better? You don't use an axe to make wood carving and you don't use a carving tool to chop wood apart.
Again, I specifically said that there is no reason that a normal home cook needs a top of the line knife. But a serious home cook will want to develop good knife skills and eventually use a good knife.