Critics are right about buyers of steel being luddites. But it's the doctrine of planned obsolescence that they're rebelling against.
Planned obsolescence or built-in obsolescence in industrial design and economics is a policy of planning or designing a product with an artificially limited useful life, so it will become obsolete, that is, unfashionable or no longer functional after a certain period of time. The rationale behind the strategy is to generate long-term sales volume by reducing the time between repeat purchases (referred to as "shortening the replacement cycle").
https://en.wikipedia.org/wiki/Planned_obsolescenceIt's got a connection with branding, especially where there's an oligopoly. The constant 'improvement' of Shimano/ Campagnolo, is the prime example in cycling.
Reynolds 531 was the paradox of a brand that didn't change for decades, winning more Tours de France than any other tubing.
http://www.cyclingweekly.co.uk/news/latest-news/icons-of-cycling-reynolds-531-tubing-199581The basis of most quality frames in the world was 531, in a number of manifestations. A full double-butted set will still feel comfortable today. It will flex, but that's a good thing in general, and everyone knew how a quality frame behaved, because they were all the same.
The 1970s cycling press didn't do tests of bikes, as technology stood still for a decade, but concentrated on riders and events. The main expression of individual choice lay in having a made-to-measure frame, with an ex-rider's name on it. The main brands were looked down on by club riders.
The result was that bicycles held a strong appeal for those who were rebelling against consumerism. There were more suppliers of components, and the basic materials enabled a 'craft' element to survive.
These attitudes were reinforced by the values of the time, when a Ford Cortina was restyled regularly, but was the same underneath, and rusted away rapidly. The modern equivalent seems to be I-phones, a short product life-cycle, with poor repairability.
I'd agree that there's a strong residue of attitudes which aren't about the ultimate performance of a consumer product at the time of purchase, and how that compares to the previous and next iterations of that product.
Luddites look at the finishing times of PBP in 1983, and wonder how much was about the bike.