Those cheap restaurant supply knives he's talking about can hold an edge just fine. They look cheap because they have that plastic handle, but they are very durable in my experience.
Durable yes, good edge retention? Not so much. Restaurants like this tend to prefer softer more durable steels, like that found in your classic Henkels (usually refereed to as German stainless). A chef's personal knives tend to be a very different style. Usually modeled after the Japanese style of knife (very thin stock, very high (62+) hrc). And the steel tends to be either carbon steel or vg-10 or better for stainless.