Everything I've read up on says pretty much the same thing; meaning pretty much nothing was mentioned about "patch" knives being used "in the day".
But, all of my several shooting bags have a patch knife sheath on the strap. It is conveniant and unless I'm actually in the field hunting, etc., I most likely don't have a sheath knife on my belt.
A dedicated patch knife is well to have a rounded tip. Much less likely to stab yourself in the process. The Green River "patch" blade or also called a paring blade is a good design because it is not too sharp at the tip and if you want it rounded is easily ground off and will still have an adequate length.
I've made those into patch knives using scales on the original shape, scales on a reground shape and ground to a narrow tang to insert into horn or whatever suits your fancy.
I made one for my grandson using the full fork of a forkhorn mule deer. Plan was to cut the forks off and form a singular handle. Did not have time to finish the job and gave it to him sheathed onto a bag I made him. Told him to bring it by the house and I'd finish it off for him. He would not hear of it and still wears the rig with that whole antler on the patch knive
This one is as simple as you can get with a piece of antler and a blade ground from a broken Sawsall blade. Total cost; about 5 cents worth of glue!