Not intended as an ad hominem as much as a reductio ad absurdum. It is frequently true that the views held by those older are also more likely to be correct, but it is not guaranteed. This is especially true when the views relate to social norms, views on which few people change as they get older. Cathedral vs Bazaar is probably as close to an argument of social norms as the software world gets...
My reading of PHK here is that Cathedrals often lead to better systems than the anarchy-bazaar that he feels has come to be most of the OSS world.
I think bazaar's like the Turkish one referenced above (with guilds and standards of quality) are the best of all worlds. but to get there, a guild needs a strong, opinionated leader. Torvalds perhaps. (PHK seems to fit the bill too :-)
So, what I suggest is the issue here, is too many people trying to build a cathedral in a bazaar - they want everyone to build it their way but cannot persuade enough others to follow them. As such the bazaar is full of many half-finished carpets instead of less, perfect carpets made by engaged teams.
Software needs many talented people, working together, mentoring new ones in "their way". A bazaar is great for getting different talented people to find each other and choose between many different projects. A Cathedral is great for encouraging apprenticeships, the promulgation of culture and so on.
It is frequently true that the views held by those older are also more likely to be correct, but it is not guaranteed.
I think that one of the best lessons to take away from this whole flame fest is that history is something to learn from, and not just blindly revere. But first, that requires knowing about history, which far too many people don't. The whole issue of whether cathedrals or bazaars produce better software is orthogonal, and needs to be addressed to different situations.
First, are there still places where cathedral style development is a very good idea, hinging on being necessary? Yes, but it has to be done right, and unfortunately, cathedrals aren't (usually) very flexible. The Mars rovers were all cathedral programmed and work pretty darn well; on the other end of the spectrum you can find all sorts of big projects that went awry, even with "coherent design".
Second, is cathedral design necessary for all software today? No. I'm fortunate enough to have the perspective of a second generation programmer; my father started in middle school by sending punch cards to the university and would get his results a week later. Careful planning was not just a good idea then; it was absolutely necessary. These days he has a computer with more power and connectivity in his pocket than was available when he was born. His turnaround time for seeing results on software changes these days is well under five minutes.
So the computing industry has come so far so fast that it's not just unnecessary to make grandiose plans in advance, it may actually be a bad idea in a number of cases (what was it Paul Graham said? "If you want a recipe for a startup that's going to die, here it is: a couple of founders who have some great idea they know everyone is going to love, and that's what they're going to build, no matter what.").
It's kind of nice that anyone can just pick up a computer and start writing software these days. Sure, sometimes it's scary too, to think of all the inefficiencies, and wrong results and security holes that plague software. But it's so nice and liberating to think: "you know what? I can do it better, I have the freedom to try to make something better." And you can develop all cathedral style if you want!
Could software be improved? Definitely! Should people learn from history? Yes, including the mistakes. Would more design and coherent vision help make better software? Maybe; go ahead and prove it (a quick note: unfortunately, the market doesn't select the best software or designs, so you will have to prove it some other way, but being successful market wise is a good start).
