...doesn't have anything to do with practicality, as you note. It's about the same thing as improving moulding design on a cabinet where the drawers already work well - it's something that's there that makes the experience more pleasant, but the practical part is covered on any basic chisel that can get around 60 hardness or reasonably close.
I saw the UK price for DIN silver steel in some cases can be $3 a KG. This is in keeping with my comment that anyone with an automated heat setup and a couple of dies (and a large industrial hammer to squash metal in them) could make a really good chisel really really cheaply.
fine edge bits on the chisels are really an issue similar to people slicing lettuce and pork chops with a 65 hardness white steel knife. It's the pleasure of the user, but if someone really cared more about slicing lettuce and pork chops than the feel of the knife, they wouldn't care about the difference between henckels and shigefusa. The real danger is that the files may not make a technically better chisel as it's easy to chase hardness and leave them chippy. Making only out of O1 or 52100 would be technically smarter.
So, where did the jones come from? I mashed a few small files and a couple of steel offcuts into tiny utility knives several years ago. The files have a "dry" feel off of the buff and just release the wire edge easier and stay more crisp. The amount that they warp would give a LV or LN fits.
I've learned a lot from passing files out to the group here - some have gone out overhard and were only protected by the unicorn, one or two has gone out underhardened (like one of yours), and I make them a little bit less thin now because nobody seems to really like that. And I make them all flat backed now even though I really like the heat treat induced bow if it's gradual. Nobody else does.