I'm currently in the process of bringing my grand father's WW2 army issue penkife back into work order and am sure it will be my edc (it's legal in the UK which is a bonus). It's plain, functional but with a lot of history.
A few years ago I had a buddy that found a knife that had been left to him by his father when he passed. Not sure how it fell out of his sight, he brought it to me to "rehabilitate". It was an old
Weidmannsheil knife from the late 50s purchased by his father when he was stationed in Germany. Although like so many others they are back now, they were out of business for some time I believe.
He wanted the blades sanded smooth and then polished out to look brand new, so I wouldn't do it. I told him to think how that knife had earned all the little rust pits, scratches on the celluloid scales, and how long it took the change in his Dad's pocket to wear down the end of the knife that sat in the coins. He let me do minor cleaning to remove the active rust, a long soak in mineral oil, and then clean out the friction area of the blades. A slight polish on the scales and I was done.
When he saw the knife I though he was going to cry. He told me it looked exactly like that (at least in his memory) when his Dad was still around, probably about 40 years ago. I have a few old ones myself, and the old traditionals I have that were either inherited or purchased by me all have value well beyond cash. My oldest work knife that I still have was purchased by me in 1976, a CASE brand large Copperhead. I was so broke most of that period in my life that I carred that knife exclusively for about 5 years, and then another 5 off and on after that. It is worn! But that is probably my most prized knife.
Is it my age

as although we are now spoilt for choice re designs, fnf and steels is there still "something" about a simple functional knife?
Yeah, I think so. If you were brought up using a knife as a tool, certainly a tool you enjoyed using and owning, it was still a tool. You didn't have to worry about today's standards: is it "drop shutty"? how fast will it deploy if I am in conflict? will the bearings themselves scar my knife? does the manufacturer/maker offer a spa treatment? if I flick it a few thousand times a week while watching TV will it work itself loose or show wear? will my friends think I am a loser because my knife has carbon steel blades? will they think my knives are crap because they aren't at least S35V (which seems to be a base line now of practical usability)?
I remember how hard it was for me to decide which traditional CASE knife to buy back in the 70s, that was it. CASE knives were the only brand besides PUMA that were carried in the sporting goods store. Options included choice of color of bone scales and model. Still, I labored before letting go of the $10 - $12 to buy one.
Now, and I am certainly guilty of this, I have more knives that I could wear out in ten lifetimes. I have favorites, but it isn't the same as pulling "old reliable" or "my knife" out of the pocket to make a toothpick, cut a water hose, make a wood plug for a screw hole, cut off a piece of "chaw" or to pick out a splinter if the edge was still in good shape. I bonded with knife in those days, and the 3 - 4 that have made it this far (including my first scout style knife given to me in 1960) are the most special. I would dump my Pumas, ZTs, and others to keep those if I had to.