When I was a teenager, back in the 1970s, I was really interested in this Bushcraft stuff. Bought two books on the subject back then. Recently became interested again, and dug those two books up to look them through again (I was amazed I still had them). Not one of them even mentions knife selection, or anything about knives. One of them discusses making knives out of stone, but that's it. Odd, isn't it?
PS The books are Bushcraft, A Serious Guide To Survival and Camping, by Richard Graves, and Outdoor Survival Skills, by Larry Dean Olsen.
I sympathize with your sentiment and agree with it in spirit, but the facts don't support your position. It's already been mentioned that Olsen uses a knife with flint, also on page 95 it shows somebody skinning a rattlesnake with a knife - there may be more, I just looked quickly.
On the first 3 pages of Graves book that I looked at, I found two knife references - page 149 says, ".....push the point of a pin or a sharp
knife immediately.............", and page 147 says, "......and with your
knife, machete or tomahawk, split off the wet outer layer...." talking about making fuzz sticks.
I think the point is, as already alluded to, having a knife with you was never an issue, you just had it. I've carried a knife of some sort or other for the last 50+ years. When I was a boy in public school, we used to play 'stretchies' at recess, boys and some of the girls. Today, if a kid is caught with a butter knife, all the bells and whistles go off!
Having a knife to perform bushcraft and various survival skills is important, however, it is probably more important to learn how to do them without a knife, for those times you may not have one!
Doc