As much as I hate to criticize Dave here, I think he missed a much bigger point about Kicad. I am guessing it is because he worked for Altium and has the perspective of a former Altium employee, seeing an open source product as a viable alternative to Altium.
The question isn't really if Altium's sales with be hurt by Kicad, or if Altium or some other PCB software vendor, or other CAD vendor will embrace Kicad as a low-end market solution.
The real question is this: what happens when projects and ideas that currently can not be realized because the availability and cost of PCB design software is a major stumbling block can perhaps be realized with because the barriers to designing a product are further lowered?
Of necessity, or perhaps in pursuit of maximum profit, companies like Altium must charge for the software, now with term-limited license agreements, which embodies the expertise of their engineers reduced into Altium code. This expertise is hard-won and is therefore sold and treated like a scarce resource.
However, as our technology becomes more complex, it requires more complex tools that in turn embody the expertise and therefore labor of those who created the tools. This adds further barriers to designing competitive products and requires more initial capital outlay, so that fewer are able to realize projects that use more complex technology.
Vendors who sell more commodity items than highly specialized PCB design software often have an incentive to break this impasse. For example, as Dave showed kicad.com is now registered by Digikey. If more people can design PCBs, well, this is going to require parts for these PCBs, hence Digikey's incentive for supporting Kicad.
The further you get into the commodity supply chain the stronger this pressure becomes. Most Chinese vendors sell commodity, almost generically sourced electronics, and as I am not familiar with any major Chinese PCB vendors of PCB CAD software, so it would seem that these Chinese vendors would have the maximum incentive to drive demand of their electronic parts by making design tools widely available.
I think a manifestation of this is the commodity PCB design companies like JLCPCB, SeeedStudio, and many others. Why charge such an absurdly low rate for PCB manufacturing? Because I think they're playing the long game of encouraging self-contained Shenzhen-based electronics design, assembly, and product delivery. They're leveraging their strength of commodity manufacture and putting it into the hands of inventors. It's likely they can partially afford to do this because of the coordination and financial support of the Chinese government.
But I think we should ask ourselves: what products and ideas are currently are we never going to see because of the high price of tools like Altium? The existence and excitement over Kicad, I think, shows at least indirectly the enthusiasm of those who might not otherwise be able to realize their ideas, even if Kicad is not even close to the level of a sophisticated package like Altium that probably embodies thousands of man-years of effort. Of course the engineers Altium need to make a living, but a economy with too much scarcity limits its growth potential. I am not a politician or economist and can't really speak how to strike a balance.