I think a lot of the controversy revolves around subcontacting parts or services versus making them yourself, in your own shop, on your own equipment.
When I see that a maker has invested in the equipment to make knives, that demonstrates that the maker has chosen to maintain a higher level of personal control. So, if a maker uses his or her own heat treat equipment, CNC mill, CNC lathe, EDM, screw machine, or whatever to maintain a high level of quality and creativity, that's great. If it keeps the price of the knife down for the consumer, that's great, too.
Not all of us can afford all of this machinery right now, or have the desire to obtain it, or even have the room to put in in our shops if we could procure it. In most instances, buying a new piece of equipment not only takes the finances, but the time in learning how to use it efficiently.
Many makers choose the path of buying the equipment as they can afford it, learning to use it , and increasing the percentage of "sole authorship" as they grow.
That's not always the case. Some makers prefer to use hand tools for just about everything - and their knives can be as good or even better than those who use lots of machinery. It's just a different way of maintaining authorship. You have to admire it!
I've chosen the former path. Investing in my own equipment and learning to use it has meant building "better" knives - not "cheaper, faster" knives. In fact, I spend more time on building a knife now than I ever have, because I can make and finish more of the parts myself. Because I can do this, I'm enjoying knifemaking more than ever.
To me, the term "sole authorship" is a lot like the term "success"..... it's a journey - not a destination.