It is indeed a strange philosophy.
I think what earlier posters really objected to was that Cornford trumpetted their "No PCBs" philosophy as a way of demonstrating that their amps were superior to mass-produced PCB-based amps.
There are very good and very bad examples of both hand-wired and PCB-based amps. I think PCB-based amps have got a bad rap for several reasons:
1) The first PCB-based amps were often very unreliable, as the first devices using new technology often are. Hand wiring had been around for years and so was proven technology.
2) Many "boutique" manufacturers (mainly in the US) have emphasized the "no PCBs" philosophy. This view is often re-inforced by the technical editors of guitar magazines who often don't know very much about electronics.
3) If you are going to build a cheap amp you will use a PCB. A cheap amp is a cheap amp using cheap parts however you make it.
4) Many tech don't like working with PCBs. The main problem with PCBs is that in most amps you need to get to both sides of the board to change a component. If you can do this easily, then PCBs can be great to work on. With the component number silk-screened on the PCB and a good schematic it is really easy to trace signals and fault find. However, releasing the PCB from the chassis can be a total pain in some amps, new Peavey amps being absolutely the worst I have come across.
Regarding hand-wired amps built on eyelet board (a la Fender) or turret board (a la old Marshall or Hiwatt) are generally very easy to service. In contrast amps built on Tag strip, like Matchless and Cornford can be a bit of a pain as the components should be crimped on the tags.
Regarding part quality, as virtually all consumer electronics use PCBs there is a far greater range of high quality parts available for PCB-based amps, not that every manufacturer goes for the highest quality parts.....
Essentially manufacturers have learnt from the mistakes of the past and there is no reason why a modern PCB-based amp should not sound as good and be as reliable (if not more so) as a hand-wired amp.