Thornton "Textbook of Footwear Manufacture" (which I have in front of me) was published in 1953.
"˜Gemming' with a strip of fabric was universally introduced into machine-welted footwear sometime between the late 50s and mid 60s. It replaced the older technique of a machine-cut welt, which was bent-up at a right ankle to accept the welt. (Illustrations taken from Thornton.)

A cut was placed from either side into the insole, those two sections were folded up and the welt was attached to that leather. This leather 'holdfast' was turned up at 90 degrees against the direction of the insole. I did enquire about the reasons, but of course as this change came about half a century ago, I did not find anybody within the shoe industry in Northampton who had actually worked with it.
Apparently that traditional method had the great disadvantage, once the insole leather dried out and with the bending of the sole from walking that the 'holdfast' tore off. Ever since the beginning of this technique the insole needed to be gemmed, not with a strip but with a piece of textile, covering the bottom of the insole in it's entirety. Once the leather tore, the glued fabric held the ridge in place. So, it was a small step to replace the full sole backer with a narrow strip.
http://www.archive.org/details/story_of_shoes_1http://www.archive.org/details/story_of_shoes_2
This film (from the early 50s, I would guess) shows the traditional way the insole was prepared (Part 1 - from 3:27 - 4:51, with the gemming clearly visible from 4:21 on).
I don't deny that probably one of the reasons for the change was cost saving. At that same time the radio valve was replaced by the transistor and (maybe a bit later) fusible interfacings were introduced into garment making. And even with the very few manufacturers who still use a floating canvas, they do their pad-stitched by machine (apart from Oxxford, I believe).
Yes, DW, I agree a well-done hand-welted shoe is superior to a machine-made one. For those, who do not know what we are talking about, here is a drawing how the holdfast is carved out of an insole:

And here is a hand-welted insole by one of the top English "˜makers':

But I have seen plenty of badly made insoles: big, big stitches (quicker) and not tightly pulled thread. Just 'handmade' is not automatically a sign of quality, it has to be well made. (I don't want to post any negative samples. I can find plenty).
I do not share your preference of Blake Rapid, as I find that row of stitching going along the insole rather irritating. (Maybe I was a Princess in a previous life and had a pea in my bed).
It's no good, throwing out the baby with the bathwater, unless one can make practical suggestions how the processes of producing items in quantity can be improved. It will need experience within a particular industry to become a production manager. An artisan maker will not do. Practical experience comes from working on the shop floor, be it shoe-, garment- or candle making. (I suppose a hand-dipped candle is superior to a factory-made one, but it leaves me, as someone who is rather indifferent about candles, totally uninvolved.)
I'm afraid, Blake ('dark Satanic mills"˜) and William Morris are dead.