I wouldn't be surprised if that statement is almost true.
Are you talking about round filed chisel or square filed?Lot of guys here frown on them and say they dull too quick. Those guys can’t sharpen them and can’t keep them out of the dirt either. Haven’t had my hand on a saw much in nearly a decade. Used to run chippers and switched to chisels. No comparison in my mind if they’re sharp. When I run them they stay sharp because I carried a lot of chains. Slightest bit dull, slapped a sharp one on. The dull chains were then easier to sharpen just with a file.